Term
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Definition
| The broad region that corresponds to the length of the thick filaments. |
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Term
|
Definition
| one of the three binding site for tRNA during translation, it holds the tRNA carrying the next amino acid to be added to the polypeptide chain; A stands for aminoacyl- tRNA site. |
|
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Term
|
Definition
| The 5' end of a pre-mRNA molecule modified by the addition of a cap of guanine nucleotide. |
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Term
|
Definition
| The body cavity in mammals that primarily houses parts of the digestive, excretory, and reproductive systems. It is separated from the more cranial thoraic cavity by the diaphragm. |
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Term
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Definition
| Nonliving chemical and physical factors in the environment. |
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Term
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Definition
| genetically determined classes of human blood that are based on the presence or absence of carbohyrdrates A and B on the surface of red blood cells. The ABO blood group phenotypes, also called blood types, are A, B, AB, and O. |
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Term
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Definition
| A plant hormone that generally acts to inhibit growth, promote, dormancy, and help the plant tolerate stressful conditions. |
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Term
|
Definition
| Genetically determined classes of human blood that are based on the presence or absence of carbohydrates A and B on the surface of red blood cells. The ABO blood group phenotypes, are also called blood types, are A, B, AB, and O. |
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Term
|
Definition
| A plant hormone that generally acts to inhibit growth, promote dormacy, and help the plant tolerate stressful conditions. |
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Term
|
Definition
| The uptake of small nutrient molecules by an organism's own body; the third main stage of food processing, following digestion. |
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Term
|
Definition
| The range of a pigments ability to absorb various wavelengths of light. |
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Term
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Definition
| The very deep benthic communities near the bottom of the ocean. This region is characterized by continuous cold, extremely high water pressure, low nutrients, and near or total absence of light. |
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Term
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Definition
| a group of ancient jawed fishes from the Devonian period. |
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Term
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Definition
| Physiological adjustment to a change in an environmental factor. |
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Term
|
Definition
| The automatic adjustment of an eye to focus on near objects. |
|
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Term
| acetyl CoA (acetyl coenzyme A) |
|
Definition
| The entry compound for the krebs cycle in cellular respiration; formed from a fragment of pyruvate attached to a coenzyme. |
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Term
|
Definition
| One of the most common neurotransmitters; functions by binding to receptors and altering the permeability of the postsynaptic membrane to specific ions, either depolarized or hyperpolarizing the membrane. |
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Term
|
Definition
| a substance that increases the hydrogen concentration of a solution. |
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Term
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Definition
| A mixture of recently swallowed food and gastric juice. |
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Term
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Definition
| rain, snow, or fog that is more acidic than pH 5.6 |
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Term
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Definition
| A solid-bodied animal lacking a cavity between the gut and outerbody wall. |
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Term
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Definition
| The discharge of a sperm's acromosome when the sperm approaches the egg. |
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Term
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Definition
| An organelle at the tip of a sperm cell that helps the sperm penetrate the egg. |
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Term
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Definition
| a globular protein that links into chains, two of which twish helically about each other, forming microfilaments in muscle and other contractile elements in cells. |
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Term
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Definition
| the class of lobefinned fishes. |
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Term
|
Definition
| The class of ray-finned fishes. |
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Term
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Definition
| A rapid change in the membrane potential of an excitable cell, caused by stimulustriggered, selective opening and closing of voltagesensitive gates in sodium and potassium ion channels. |
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Term
|
Definition
| A profile of the relative performance of different wavelengths of light. |
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Term
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Definition
| The amount of energy that reactants must absorb before a chemical reaction will start. |
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Term
|
Definition
| A transription factor that binds to an enhancer and stimulates transcription of a gene. |
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Term
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Definition
| Immunity conferred by recovering from an infectious disease. |
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Term
|
Definition
| The specific portion of an enzyme that attaches to the substrate by means of weak chemical bonds. |
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Term
|
Definition
| The specific portion of an enzyme that attaches to the substrate by means of weak chemical bonds. |
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Term
|
Definition
| The movement of a substance across a biological membrane against its concentration or electrochemical gradient with the help of energy input and specific transport proteins. |
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Term
|
Definition
| An equilibrium state in a population when the gene pool has allele frequencies that maximize the average fitness of a population's members. |
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Term
|
Definition
| The emergence of numerous species from a common ancestor introduced into an environment, presenting a diversity of new opportunities and problems. |
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Term
|
Definition
| Also called the anterior pituitary, it consits of endocrine cells that synthesize and secrete several hormones directly into the blood. |
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Term
|
Definition
| An enzyme that converts ATP to cyclic AMP in response to a chemical signal. |
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Term
|
Definition
| The attraction between different kinds of molecules. |
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Term
|
Definition
| An endocrine gland located adjacent to the kidney in mammals; composed of two glandular portions; an outer cortex, which responds to endocrine signals in reacting to stress and effecting salt and water balance, and a central medulla, which responds to nervous inputs resulting from stress. |
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Term
|
Definition
| The central portion of an adrenal gland, controlled by nerve signals, that secretes the fight or flight hormones epinephrine and norepinphrine. |
|
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Term
| adrenocorticotropic hormone |
|
Definition
| A peptide hormone released from the anterior pituitary, it stimulates the production and secretion of steroid hormones by the adrenal cortex. |
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Term
|
Definition
| Roots extending from stems and leaves above ground. |
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Term
|
Definition
| Containing oxygen; referring to an organism, environment, or cellular process that requires oxygen. |
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Term
|
Definition
| The blood vessel supplying a nephron. |
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Term
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Definition
| A branch of mammals that includes sloths, anteaters, and armadillos. |
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Term
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Definition
| The relative number of individuals of each age in a population. |
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Term
|
Definition
| An antibody-mediated immune response in which bacteria or viruses are clumped together, effectively neutralized, and opsonized. |
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Term
|
Definition
| A fruit such as a blackberry that develops from a single flower that has several carpels. |
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Term
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Definition
| A member of a jawless class of vertebrates represented today by the lampreys and hagfishes. |
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Term
|
Definition
| A type of behavior involving a contest of some kind that determines which competitor gains access to some resource, such as food or mates. |
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Term
| AIDS (acquired immunodeficiency syndrome) |
|
Definition
| The name of the late stages of HIV infection; defined by a specified reduction of T cells and the appearance of characteristic secondary infections. |
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Term
|
Definition
| The conversion of pyruvate to carbon dioxide and ethyl alcohol. |
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Term
|
Definition
| Organic compounds containing hydroxyl groups. |
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Term
|
Definition
| An organic molecule with a carbonyl group located at the end of the carbon skeleton. |
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Term
|
Definition
| An adrenal hormone that acts on the distal tubules of the kidney to stimulate the reabsorption of the sodium (Na+) and the passive flow of water from the filtrate. |
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Term
|
Definition
| A photosynthetic plantlike protist. |
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Term
|
Definition
| A digestive tract consisting of a tube running between a mouth and an anus. |
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Term
|
Definition
| One of the four extra-embryonic membranes; serves as a repository for the embryo's nitrogenous waste. |
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Term
|
Definition
| Alternate versions of a gene. |
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Term
|
Definition
| The variation in the relative rates of growth of various parts of the body, which helps shape the organism. |
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Term
|
Definition
| A mode of speciation induced when the ancestral population becomes segregated by a geographic barrier. |
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Term
|
Definition
| A common type of polypoid species resulting from two different species interbreding and combining their chromosomes. |
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Term
|
Definition
| An action that occurs either completely or not at all, such as the generation of an action potential by a neutron. |
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Term
|
Definition
| A specific receptor site on some part of an enzyme molecule remote from the active site. |
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Term
|
Definition
| A spiral shape constituting one form of the secondary structure of proteins, arising from a specific hydrogen-bonding structure. |
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Term
|
Definition
| A harmless variant or derivative of a pathogen that stimulates a host's immune system to mount defenses against the pathogen. |
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Term
| alternation of generations |
|
Definition
| A life cycle in which there is both a multicellular diploid form, the sporophyte, and a multicellular haploid form, the gametophyte; characteristic of plants. |
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Term
|
Definition
| A type of regulation at the RNA- processing level in which different mRNA molecules are produced from the same primary transcript depending on which RNA segments are treated as exons ans which as introns. |
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Term
|
Definition
| Behavior that reduces an individual's fitness while increasing the fitenss of another individual. |
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Term
|
Definition
| The aiding of another individual at one's own risk or expense. |
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Term
|
Definition
| A protistan clade that includes dinoflagellates, apicocomplexans, and the ciliates. Alveolates have small membrane-bounded cavities called alveoli under their cell surfaces. The function of alveoli is unknown. |
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Term
|
Definition
(1)One of the deadend, multilobed air sacs that constitute the gas exchange surface of the lungs.
(2)One of the milksecreting sacs of epithelial tissue in the mammary glands. |
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Term
|
Definition
| Neutrons of the retina help integrate information before it is sent to the brain. |
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Term
|
Definition
| An organic compound with the one or more amino groups. |
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|
Term
|
Definition
| An organic compound with one or more amino groups. |
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Term
|
Definition
| An organic molecule possessing both carboxyl and amino groups. Amino acids serve as the monomers of proteins. |
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Term
|
Definition
| A functional group that consists of a nitrogen atom bounded to two hyrdrogen atoms; can act as a base in solution, accepting a hydrogen ion and acquiring a charge of +1. |
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|
Term
| aminoacyl-tRNA synthesase |
|
Definition
| An enzyme that joins each amino acid to the correct tRNA. |
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|
Term
|
Definition
| An enzyme found within the snall intestine that splits off one amino acid at a time, beginning at the opposite end of the polypeptide containing a free carboxyl group. |
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Term
|
Definition
| A small and very toxic nitrogenous waste produced by metabolism. |
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Term
|
Definition
| Shelled cephalopod animals that were the dominant invertebrate predators for millions of years ending with themass extinctions at the end of the Cretaceous period. |
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Term
|
Definition
| A technique for determining genetic abnormalities in a fetus by the presence of certain chemicals or defective fetal cells in the amniotic fluid, obtained by aspiration from a needle inserted into the uterus. |
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Term
|
Definition
| The innermost of four extraembryonic membranes; encloses a fluid-filled sac in which the embryo is suspended. |
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Term
|
Definition
| A vertebrate possessing an amnion surrounding the embryo; reptiles, birds, and mammals are amniotes. |
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Term
|
Definition
| A shelled, water-retaininig egg that enables reptiles, birds, and egg-laying mammals to complete their life cycles on dry land. |
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Term
|
Definition
| A type of protist characterized by great flexibility and the presence of pseudopodia. |
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Term
|
Definition
| An amoebalike cell that moves by pseudopodia, found in most animals; depending on the species, may digest and distribute food, dispose of wastes, form skeletal fibers, fight infections, and change into other cell types. |
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Term
|
Definition
| An amoebalike cell that moves by pseudopodia, found in most animals; depending on the species, may digest and distribute food, dispose of wastes, form skeletal fibers, fight infections, and change into other cell types. |
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Term
|
Definition
| The vertebrate class of amphibians, represented by frogs, salamanders, and caecilians. |
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Term
|
Definition
| A molecule that has both a hydrophillic region and a hydrophobic region. |
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Term
|
Definition
| The strengthening of stimulus energy that is otherwise too weak to be carried into the nervous system. |
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Term
|
Definition
| A metabollic pathway that synthesizes a complex molecule from simpler compounds. |
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Term
|
Definition
| lacking oxygen; referring to an organism, environment, or cellular process that lacks oxygen to accept electrons at the "downhill" end of electron transport chains. |
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Term
|
Definition
| A pattern of evolutionary change involving the transformation of an entire population, sometimes to a state different enough from the ancestral population to justify renaming it as a separate species; also called phyletic evolution. |
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Term
|
Definition
| The similarity of structure between two species that are not closely related; attributable to convergent evolution. |
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Term
|
Definition
| the fourth subphase of mitosis, in which the chromatids of each chromosome have separated and the daughter chromosomes are moving to the poles of the cell. |
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Term
|
Definition
| An acute, life threatening, allergic response. |
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Term
|
Definition
| One of three groups of amniotes based on key differences between their skulls. |
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Term
| anatomically modern humans |
|
Definition
|
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Term
|
Definition
| The study of the structure of an organism. |
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Term
|
Definition
| The requirement that to divide, a cell must be attached to the substratum. |
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Term
|
Definition
| The principal male steroid hormones, such as testosterone, which stimulate the development and maintenance of the male reproductive system and secondary sex characteristics. |
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Term
|
Definition
| A chromosomal aberration in which certain chromosomes are present in extra copies or are deficient in number. |
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Term
|
Definition
| A flowering plant, which forms seeds inside a protective chamber called an ovary. |
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Term
|
Definition
| The ability to survive in a dormant state when an organism's habitat dries up. Also called cryptobiosis. |
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Term
|
Definition
| The portion of the egg where the least yolk is concentrated. Opposite of the veggetal pole. |
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Term
|
Definition
| A negatively charged ion. |
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Term
|
Definition
| A plant that completes its entire life cycle in a single year or growing season. |
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Term
|
Definition
| Sensory appendages found in uniramians and crustaceans. |
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Term
|
Definition
| Referring to the head end of a bilaterally symmetrical animal. |
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Term
|
Definition
| Also called the adenohypophysis, it consists of endocrine cells that synthesize and secrete several hormones directly into the blood. |
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Term
|
Definition
| Ther terminal pollen sac of a stamen, inside which pollen grains with male gametes form in the flower of an angiosperm. |
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Term
|
Definition
| In plants, the male gametangium, a moist chamber in which gametes develop. |
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Term
|
Definition
| The phylum of hornworts, small herbaccous (nonwoody) plants. |
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Term
|
Definition
| The phylum containing all angiosperms. |
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Term
|
Definition
| A member of a primate group made up of the apes (gibbon, orangutan, gorilla, chimpanzee, and bonobo), monkeys, and humans. |
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Term
|
Definition
| A chemical that kills bacteria or inhibits growth. |
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Term
|
Definition
| An antigen-binding immunoglobulin produced by B cells, that functions as the effector in an immune response. |
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Term
|
Definition
| A specialized base triplet at one end of a tRNA molecule that recognizes a particular complementary codon on an mRNA molecule. |
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Term
|
Definition
| A hormone that is part of an elaborate feedback scheme that helps regulate the osmolarity of the blood. |
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Term
|
Definition
| A foreign macromolecule that does not belong to the host organism and that elicits an immune response. |
|
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Term
|
Definition
| The process by which an MHC molecule cradles a fragment of an intercellular protein antigen in its hammocklike groove, carries it to the cell surface, and "presents the protein to an antigen receptor on a nearby T cell. |
|
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Term
|
Definition
| Transmembrane versions of antibody molecules that B cells and T cells use to recognize specific antigens. Also called membrane antibodies. |
|
|
Term
| antigen-presenting cell (APC's) |
|
Definition
| Cells that ingest bacteria and viruses and then destroy them. Class II MHC molecules in these cells collect peptide remnants of this degradation and present them to help T cells. |
|
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Term
|
Definition
| The order of frogs and toads that includes tailless tetrapod amphibians. |
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Term
|
Definition
| The group of frogs and toads. |
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Term
|
Definition
| The part of the ocean beneath the photic zone, where light does not penetrate sufficiently for photosynthesis to occur. |
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Term
|
Definition
| Concentration of growth at the tip of a plant shoot, where a terminal bud partially inhibits axillary bud growth. |
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Term
|
Definition
| A limp-bud organizing region consisting of a thickened area of ectoderm at the tip of a limp bud. |
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Term
|
Definition
| Embryonic plant tissure in the tips of roots and in the buds of shoots that supplies cells for the plant to grow in length. |
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Term
|
Definition
| One of a group of parasitic protozoans, some of which cause human diseases. |
|
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Term
|
Definition
| The order of caecilians that includes legless amphibians. |
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Term
|
Definition
|
|
Term
|
Definition
| The asexual production of seeds. |
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Term
|
Definition
| A derived phenotypic character, or homology, that evolved after a branch derived from a phylogenetic tree. |
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Term
|
Definition
| In plants, the nonliving continuum formed by the extracellular pathway provided by the continuous matrix of cell walls. |
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Term
|
Definition
| Programmed cell death brought about by signals that trigger the activation of a cascade of "suicide" proteins in the cells destined to die. |
|
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Term
|
Definition
| The bright coloration of animals with effective physical or chemical defenses that acts as a werning to predators. |
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Term
|
Definition
| A small, fingerlike extension of the vertebrate cecum; contains a mass of white blood cells that contribute to immunity. |
|
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Term
|
Definition
| A transport protein in the plasma membrane of a plant or animal cell that specifially facilitates the diffusion of water across the membrane.(osmosis) |
|
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Term
|
Definition
| Plasmalike liquid in the space between the lens and the cornea in the vertebrate eye; helps maintain the shape of the eye, supplies nutrients and oxygen to its tissues, and disposes of its wastes. |
|
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Term
|
Definition
| A solution in which water is the solvent. |
|
|
Term
|
Definition
| The animal class that includes scorpions, spiders, ticks, and mites. |
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Term
|
Definition
| One of two prokaryotic domains, the other being the Bacteria. |
|
|
Term
|
Definition
| Primitive eukaryotic group that includes diplomonads, such as Giardia; some systematists assign kingdom status to archezoans. |
|
|
Term
| archegonium (plural, archegonia) |
|
Definition
| In plants, the female gametangium, a moist chamber in which gametes develop. |
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Term
|
Definition
| The endoderm-lined cavity, formed during the gastrulation process, that develops into the digestive tract of an animal. |
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Term
|
Definition
| The reptilian group that includes crocodiles, alligators, dinosaurs, and birds. |
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Term
|
Definition
| A vessel that conveys blood between an artery and a capillary bed. |
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Term
|
Definition
| A cardiovascular disease caused by the formation of hard plaques within the arteries. |
|
|
Term
|
Definition
| A vessel that carries blood away from the heart to organs throughout the body. |
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|
Term
|
Definition
| Segmented coelomates with exoskeletons and jointed appendages. |
|
|
Term
|
Definition
| The most diverse phylum in the animal kingdom; includes the horseshoe crabm arachnids (e.g., spiders, ticks, scorpions, and mites) , crustaceans (e.g., crayfish, lobsters, crabs, barnacles), millipedes, centipedes, and insects. Arthropods are characterized by a chitinous exoskeleton, molting, jointed appendages, and a body formed of distinct groups of segments. |
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Term
|
Definition
| The selective breeding of domesticated plants and animals to encourage the ocurrence of desirable traits. |
|
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Term
|
Definition
| Macroscopic fruiting bodies of sac fungi. |
|
|
Term
|
Definition
| A saclike spore capsule located at the tip of the asocarp in dikaryotic hyphae; defining feature of the Ascomycota division of fungi. |
|
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Term
|
Definition
| A type of reproduction involving only one parent that produces genetically identical offspring by budding or by the division of a single cell or the entire organism into two or more parts. |
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Term
|
Definition
| An amino acid that functions as a CNS neurotransmitter. |
|
|
Term
|
Definition
| The acquired ability to associate one stimulus with another; also called classical conditioning. |
|
|
Term
|
Definition
| A type of nonrandom mating in which mating partners resemble each other in certain phenotypic characters. |
|
|
Term
|
Definition
| Glial cells that provide structural and metabolic support for neurons. |
|
|
Term
|
Definition
| A carbon atom covalently bonded to four different atoms or groups of atoms. |
|
|
Term
|
Definition
| Cell division in which one daughter cell receives more cytoplasm than the other during mitosis. |
|
|
Term
|
Definition
| A cardiovascular disease in which growths called plaques develop on the inner walls of the arteries, narrowing their inner diameters. |
|
|
Term
|
Definition
| The smallest unit of matter that retains the properties of an element. |
|
|
Term
|
Definition
| An atom's core, containing protons and neutrons. |
|
|
Term
|
Definition
| The number of protons in the nucleus of an atom, unique for each element and designated by a subscript to the left of the elemental symbol. |
|
|
Term
|
Definition
| The total atomic mass, which is the mass in grams of one mole of the atom. |
|
|
Term
| ATP (adenosine triphosphate) |
|
Definition
| An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells. |
|
|
Term
|
Definition
| A cluster of several membrane proteins found in the mitochondrial crista (and bacterial plasma membrane) that function in chemiosmosis with adjacent electron transport chains, using the energy of a hydrogen ion concentration gradient to make ATP. ATP synthases provide a port through which hyrdrogen ions diffuse into the matrix of a mitochondrion. |
|
|
Term
| atrial natriuretic factor |
|
Definition
| A peptide hormone that opposes the renin-angiotensin-aldosterone system (RAAS). |
|
|
Term
|
Definition
| A valve in the heart between each atrium and ventricle that prevents a backflow of blood when the ventricles contract. |
|
|
Term
|
Definition
| A chamber that receives blood returning to the vertebrate heart. |
|
|
Term
|
Definition
| According to this model, eukaryotic cells evolved by the specialization of internal membranes originally derived from prokaryotic plasma membranes. |
|
|
Term
|
Definition
| An immunological disorder in which the immune system turns against itself. |
|
|
Term
|
Definition
| A subdivision of the motor nervous system of vertebrates that regulates the internal environment; consists of the sympathetic and parasympathetic divisions. |
|
|
Term
|
Definition
| A type of polyploid species resulting from one species doubling its chromosome number to become tetraploid, which may self-fertilize or mate with other tetraploids. |
|
|
Term
|
Definition
| A chromosome that is not directly involved in determining sex, as opposed to a sex chromosome. |
|
|
Term
|
Definition
| An organism that obtains organic food molecules without eating other organisms or substances derived from other organisms. Autotrophs use energy from the sun or from the oxidation of inorganic substances to make organic molecules from inorganic ones. |
|
|
Term
|
Definition
| A class of plant hormones, including indoleacetic acid (IAA), having a variety if effects, such as phototropic response through the stimulation of cell elongation, stimulation of secondary growth, and the development of leaf traces and fruit. |
|
|
Term
|
Definition
| A nutritional mutant that is unable to synthesize and that cannot grow on media lacking certain essential molecules normally synthesized by wild-type strains of the same species. |
|
|
Term
|
Definition
| The vertebrate class of birds, characterized by feathers and other flight adaptations. |
|
|
Term
|
Definition
| A structure that has the potential to form a vegetative branch. The bud appears in the angle formed between a leaf and a stem. |
|
|
Term
|
Definition
| A typically long extension, or process from a neuron that carries nerve impulses away from the cell body toward target cells. |
|
|
Term
|
Definition
| A type of lymphocyte that develops in the bone marrow and later produces antibodies, which mediate humoral immunity. |
|
|
Term
|
Definition
| One of two prokaryotic domains, the other being the Archaea. |
|
|
Term
| bacterial artificial chromosome (BAC) |
|
Definition
| An artificial version of a bacterial chromosome that can carry inserts of 100,000- 500,000 base pairs. |
|
|
Term
|
Definition
| A virus that infects bacteria; also called a phage. |
|
|
Term
|
Definition
| A photosynthetic pigment found in halophiles. It is very similar to the visual pigments in the retinas of our eyes. |
|
|
Term
| bacterium (plural, bacteria) |
|
Definition
| A prokaryotic microorganism in Domain Bacteria. |
|
|
Term
|
Definition
| A form of Rhizobium contained within the vesicles formed by the root cells of a root nodule. |
|
|
Term
|
Definition
| A bone that is contained in, and helps stiffen, the penis of rodents, raccoons, walruses, and several other mammals. |
|
|
Term
|
Definition
| The ability of natural selection to maintain diversity in a population. |
|
|
Term
|
Definition
| All tissues external to the vascular cambium in a plant growing in thickness, consisting of phloem, phelloderm, cork cambium, and cork. |
|
|
Term
|
Definition
| A dense object lying along the inside of the nuclear envelope in female mammalian cells, representing an inactivated X chromosome. |
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Term
|
Definition
| Contraception that relies upon a physical barrier to block the passage of sperm. Examples include condoms and diaphragms. |
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Term
|
Definition
| Glands near the vaginal opening in a human female that secrete lubricating fluid during sexual arousal. |
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Term
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Definition
| A eukaryotic cell organelle consisting of a 9 + 0 arrangement of microtubule triplets; may organize the microtubule assembly of a cilium or flagellum; structurally identical to a centriole. |
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Term
| basal metabolic rate (BMR) |
|
Definition
| The minimal number of kilocalories a resting animal requires to fuel itself for a given time. |
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Term
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Definition
| A cluster of nuclei deep within the white matter of the cerebrum. |
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Term
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Definition
| A substance that reduces the hydrogen ion concentration of a solution. |
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Term
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Definition
| The floor of an epithelial membrane on which the basal cells rest. |
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Term
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Definition
| A point mutation; the replacement of one nucleotide and its partner in the complementary DNA strand by another pair of nucleotides. |
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Term
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Definition
| Elaborate fruiting bodies of a dikaryotic mycelium of a club fungus. |
|
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Term
| basidium (plural, basidia) |
|
Definition
| A reproductive appendage that produces sexual spores on the gills of mushrooms. The fungal division Basidiomycota is named for this structure. |
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Term
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Definition
| A circulating leukocyte that produces histamine. |
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Term
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Definition
| A type of mimicry in which a harmless species looks like a species that is poisonous or otherwise harmful to predators. |
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Term
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Definition
| What an animal does and how it does it. |
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Term
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Definition
| A heuristic approach based on the expecation that Darwinian fitness (reproductive success) is improved by optimal behavior. |
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Term
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Definition
| A mass of abnormal cells that remains at the site of origin. |
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Term
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Definition
| The bottom surfaces of aquatic environments. |
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Term
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Definition
| The communities of organisms living in the benthic zone of an aquatic biome. |
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Term
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Definition
| The source of insulin within the islets of Langerhans, nestled within the pancreas. |
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Term
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Definition
| A metabolic sequence that breaks fatty acids down to two-carbon fragments which enter the Krebs cycle as acetyl CoA. |
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Term
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Definition
| One form of the secondary structure of proteins in which the polypeptide chain folds back and forth, or where two regions of the chain lie parallel to each other and are held together by hydrogen bonds. |
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Term
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Definition
| A plant that requires two years to complete its life cycle. |
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Term
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Definition
| A life history in which adults have but a single reproductive opportunity to produce large numbers of offspring, such as the life history of the Pacific salmon. Also known as semelparity. |
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Term
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Definition
| Characterizing a body from with a central longitudinal plane that divides the body into two equal but opposite halves. |
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Term
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Definition
| Members of the branch of eumetazoans possessing bilateral symmetry. |
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Term
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Definition
| A mixture of substances that is produced in the liver, stored in the gall bladder, and acts as a detergent to aid in the digestion and absorption of fats. |
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Term
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Definition
| The type of cell division by which prokaryotes reproduce. Each dividing daughter cell receives a copy of the single parental chromosome. |
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Term
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Definition
| The two-part latinized name of a species, consisting of genus and specific epithet. |
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Term
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Definition
| A relatively small area with an exceptional concentration of endemic species. |
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Term
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Definition
| The study of how organisms manage their energy resources. |
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Term
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Definition
| The principle that all life arises by the reproduction of preexisting life. |
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Term
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Definition
| Neurotransmitters derived from amino acids. |
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Term
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Definition
| Any of the various nutrient circuits, which involve both biotic and abiotic components of ecosystems. |
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Term
|
Definition
| The study of the past and present distribution of species. |
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Term
|
Definition
| An internal timekeeper that controls an organism's biological rhythms; marks time with or without environmental cues but often requires signals from the environment to remain tuned to an appropriate period. (See also circadian rhythm) |
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Term
|
Definition
| A trophic process in which retained substances become more concentrated with each link in the fod chain. |
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Term
| biological species concept |
|
Definition
| The definition of a species as a population or group of populations whose members have the potential in nature to interbreed and produce fertile offspring; a biological species is also called a sexual species. |
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Term
|
Definition
| The dry weight of organic matter comprising a group of organisms in a particular habitat. |
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Term
|
Definition
| One of the world's major ecosystems, classified according to the predominant vegetation and characterized by adaptations of organisms to that particular environment. |
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Term
|
Definition
| The use of living organisms to detoxify and restore polluted and degraded ecosystems. |
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Term
|
Definition
| The manipulation of living organisms to detoxify and restore pollutedd and degraded ecosystems. |
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Term
|
Definition
| The entire portion of Earth inhabited by lfe; the sum of all the planet's ecosystems. |
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Term
|
Definition
| The manipulation of living organisms or their components to produce useful products. |
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Term
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Definition
| pertaining to the living organisms in the environment. |
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Term
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Definition
| All the organisms that are part of the environment. |
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Term
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Definition
| Neurons that synapse with the axons of rods and cones in the retina of the eye. |
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Term
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Definition
| Chemical contraceptives that inhibit ovulation, retard follicular development, or alter a woman's cervical mucus to prevent sperm from entering the uterus. |
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Term
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Definition
| A flower equipped with both stamens and carpels. |
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Term
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Definition
| A leaflike structure of a seaweed that provides most of the surface area for photosynthesis. |
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Term
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Definition
| The fluid-filled cavity that forms in the center of the blastula embryo. |
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Term
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Definition
| An embryonic stage in mammals; a hollow ball of cells produced one week after fertilization in humans. |
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Term
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Definition
| An embryonic cap of dividing cells resting on a large undivided yolk. |
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Term
|
Definition
| Small cells of an early embryo. |
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Term
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Definition
| The opening of the archenteron in the gastrula that develops into the mouth in protostomes and the anus in deuterostomes. |
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Term
|
Definition
| The hollow ball of cells marking the end stage of cleavage during early embryonic development. |
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Term
|
Definition
| A type of connective tissue with a fluid matrix called plasma in which blood cells are suspended. |
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Term
|
Definition
| The hydrostatic force that blood exerts against the wall of a vessel. |
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Term
|
Definition
| A set of tubes through which the blood moves through the body. |
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Term
|
Definition
| A specialized capillary arrangement in the brain that restricts the passage of most substances into the brain, thereby preventing dramatic fluctuations in the brain's environment. |
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Term
|
Definition
| A fluid-containing space between the digestive tract and the body wall. |
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Term
|
Definition
| A lubricated ball of chewed food. |
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Term
|
Definition
| The quantity of energy that must be absorbed to break a particular kind of chemical bond; equal to the quantity of energy the bond releases when it forms. |
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Term
|
Definition
| A type of connective tissue, consisting of living cells held in a rigid matrix of collagen fibers embedded in calcium salts. |
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Term
|
Definition
| Organs of gas exchange in spiders, consisting of stacked plates contained in an internal chamber. |
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Term
|
Definition
| Genetic drift resulting from the reduction of a population, typically by a natural disaster, such that the surviving population is no longer genetically representative of the original population. |
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Term
|
Definition
| A model of community organization in which mineral nutrients control community organization because nutrients control plant numbers, which in turn control herbivore numbers, which in turn control predator numbers. |
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Term
|
Definition
| A cup-shaped receptacle in the vertebrate kidney that is the initial, expanded segment of the nephron where filtrate enters from the blood. |
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Term
|
Definition
| Also called lamp shells, these animals superficially resemble clams and other bivalve mollusks, but the two halves of the brachipod shell are dorsal and ventral to the animal rather than lateral, as in clams. |
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Term
|
Definition
| A hormone produced by neurosecretory cells in the insect brain. It promotes development by stimulating the prothoractic glands to secrete ecdysone. |
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Term
|
Definition
| The hindbrain and midbrain of the vertebrate central nervous system. In humans, it forms a cap on the anterior end of the spinal cord, extending to about the middle of the brain. |
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Term
|
Definition
| A brain center that directs the activity of organs involved in breathing. |
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Term
|
Definition
| Fine branches of the bronchus that transport air to alveoli. |
|
|
Term
| bronchus (plural, bronchi) |
|
Definition
| One of a pair of breathing tubes that branch from the trachea into the lungs. |
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Term
|
Definition
| One of a group of marine, multicellular, autotrophic protists, the most common type of seaweed. Brown algae include the kelps. |
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Term
|
Definition
| A special tissue in some mammals, located in the neck and between the shoulders, that is specialized for rapid heat production. |
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Term
|
Definition
| The phylum of mosses. Note that the term "bryophyte" refers instead to the informal group of mosses, liverworts, and hornworts. |
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Term
|
Definition
| A moss, liverwort, or hornwort; a nonvascular plant that inhabits the land but lacks many of the terrestrial adaptations of vascular plants. |
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Term
|
Definition
| Colonial animals that superficially resemble mosses. |
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Term
|
Definition
| An asexual means of propagation in which outgrowths from the parent form and pinch off to live independently or else remain attached to eventually form extensive colonies. |
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Term
|
Definition
| Used in reference to the gains and losses of various materials and energy. Most energy and materials budgets are interconnected, with changes in the flux of one component affecting the exchanges of other components. |
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Term
|
Definition
| A substance that consists of acid and base forms in a solution and that minimizes changes in pH when extraneous acids or bases are added to the solution. |
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Term
|
Definition
| One of a pair of glands near the base of the penis in the human male that secretes fluid that lubricates and neutralizes acids in the urethra during sexual arousal. |
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Term
|
Definition
| The movement of water due to a difference in pressure between two locations. |
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Term
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Definition
| Animals that eat relatively large pieces of food. |
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Term
|
Definition
| A type of photosynthetic cell arranged into tightly packed sheaths around the veins of a leaf. |
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Term
|
Definition
| A plant that uses the Calvin cycel for the initial steps that incorporate CO2 into organic material, forming a three-carbon compound as the first stable intermediate. |
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Term
|
Definition
| A plant that prefaces the Calvin cycle with reactions that incorporate CO2 into four-carbon compounds, the end product of which supplies CO2 for the Calvin cycle. |
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Term
|
Definition
| An important class of cell-to-cell adhesion molecules. |
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Term
|
Definition
| A mammalian thyroid hormone that lowers blood calcium levels. |
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Term
|
Definition
| A mass of dividing, undifferentiated cells at the cut end of a shoot. |
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Term
|
Definition
| An intracellular protein to which calcium binds in its function as a second messenger in hormone action. |
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Term
|
Definition
| The amount of heat energy required to raise the temperature of 1 g of water by 1degC; also the amount of heat energy that 1 g of water releases when it cools by 1degC. The Calorie (with a capital C), usually used to indicate the energy content of food, is a kilocalorie. |
|
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Term
|
Definition
| The second of two major stages in photosynthesis (following the light reactions), involving atmospheric CO2 fixation and reduction of the fixed carbon into carbohyrdrate. |
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Term
|
Definition
| A plant that uses crassulacean acid metabolism, an adaptation for photosynthesis in arid conditions, first discovered in the family Crassulaceae. Carbon dioxide entering open stomata during the night is converted into organic acids, which release CO2 for the Calvin cycle during the day, when stomata are closed. |
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Term
|
Definition
| A burst of evolutionary origins when most of the major body plans of animals appeared in a relatively brief time in geologic history; recorded in the fossil record about 545 to 525 million years ago. |
|
|
Term
| cAMP receptor protein (CRP) |
|
Definition
| A regulatory protein that directly stimulates gene expression. |
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Term
|
Definition
| The uppermost layer of vegetation in a terrestrial biome. |
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Term
|
Definition
| A microscopic blood vessel that penetrates the tissues and consists of a single layer of endothelial cells that allows exchange between the blood and interstitial fluid. |
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Term
|
Definition
| A network of capillaries that infiltrate every organ and tissue in the body. |
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Term
|
Definition
| The protein shell that encloses a viral genome. It may be rod-shaped, polyhedral, or more complete in shape. |
|
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Term
|
Definition
| A sticky layer that surrounds the cell walls of some bacteria, protecting the cell surface and sometimes helping the glue to surfaces. |
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|
Term
|
Definition
| A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides). |
|
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Term
|
Definition
| The incorporation of carbon from CO2 into an organic compound by an autotrophic organism (a plant, another photosynthetic organism, or a chemoautotrophic bacterium). |
|
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Term
|
Definition
| A functional group present in aldehydes and ketones and consisting of a carbon atom double-bonded to an oxygen atom. |
|
|
Term
|
Definition
| A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group. |
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Term
|
Definition
| An organic comound containing a carboxyl group. |
|
|
Term
|
Definition
| An enzyme found within the small intestine that splits off one amino acid at a time, beginning at the end of the polypeptide that has a free caboxyl group. |
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Term
|
Definition
| A chemical agent that causes cancer. |
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Term
|
Definition
| The alternating contractions and relaxations of the heart. |
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Term
|
Definition
| A type of muscle that forms the contractile wall of the heart; its cells are joined by intercalated discs that relay each heartbeat. |
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Term
|
Definition
| The volume of blood pumped per minute by the left ventricle of the heart. |
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Term
|
Definition
| Diseases of the heart and blood vessels. |
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Term
|
Definition
| A closed circulatory system with a heart and branching network of arteries, capillaries, and veins; the system is characteristic of vertebrates. |
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Term
|
Definition
| The group of brirds with a carina, or sternal keel, supporting their large breast muscles. |
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Term
|
Definition
| An animal, such as a shark, hawk, or spider, that eats other animals. |
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Term
|
Definition
| an accessory pigment, either yellow or orange, in the chloroplasts of plants, By absorbing wavelengths of light that chlorophyll cannot, carotenoids broaden the spectrum of colors that can drive photosynthesis. |
|
|
Term
|
Definition
| The female reproductive organ of a flower, consisting of the stigma, style, and ovary. |
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Term
|
Definition
| In human genetics, an individual who is heterozygous at a given getic locus, with one normal allele and one potentially harmful recessive allele. The heterozygote is phenotypically normal for the character determined by the gene but can pass on the harmful allele to offspring. |
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Term
|
Definition
| The maximum population size that can be supported by the available resources, symbolized as K. |
|
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Term
|
Definition
| A type of flexible connective tissue with an abundance of collagenous fibers embedded in chondrin. |
|
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Term
|
Definition
| A water-impermeable ring of wax around endodermal cells in plants that blocks the passive flow of water and solutes into the stele by way of cell walls. |
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Term
|
Definition
| A metabolic pathway that releases energy by breaking down complex molecules to simpler compounds. |
|
|
Term
| catabolite activator protein (CAP) |
|
Definition
| In E. coli, a helper protein that stimulates gene expression by binding within the promoter region of an operon and enhancing the promoter's ability to associate with RNA polymerase. |
|
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Term
|
Definition
| A chemical agent that changes the rate of a reaction without being consumed by the reaction. |
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Term
|
Definition
| The hypothesis by Georges Cuvier that each boundary between strata corresponded in time to a catastrophe, such as a flood or drought, that had destroyed many of the species living there at that time. |
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Term
|
Definition
| A class of compounds, including epinephrine and norephrine, that are synthesized from the amino acid tyrosine. |
|
|
Term
|
Definition
| An ion with a positive charge, produced by the loss of one or more electrons. |
|
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Term
|
Definition
| A process in which positively charged minerals are made available to a plant when hydrogen ions in the soil displace mineral ions from the clay particles. |
|
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Term
|
Definition
| A T cell surface protein, present on most helper T cells, CD4 binds to part of the class II MHC protein. |
|
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Term
|
Definition
| A T cell surface protein that enhances the interaction between the antigen-presenting infected cell and a cytotoxic T cell. |
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Term
|
Definition
| A limited gene library using complimentary DNA. The library includes only the genes that were transcribed in the cells examined. |
|
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Term
|
Definition
| A blind outpocket of a hollow organ such as an intestine. |
|
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Term
|
Definition
| Glycoproteins that contribute to cell migration and stable tissue structure. |
|
|
Term
|
Definition
| The part of a cell, such as a neuron, that houses the molecules. |
|
|
Term
|
Definition
| A region in the cytoplasm near the nucleus from which microtubules originate and radiate. |
|
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Term
|
Definition
| An ordered sequence of events in the life of a eukaryotic cell, from its origin in the division of a parent cell until its own division into two; composed of the M, G1, S, and G2 phases. |
|
|
Term
| cell system control system |
|
Definition
| A cyclically operating set of molecules in the cell that triggers and coordinates key events in the cell cycle. |
|
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Term
|
Definition
| The reproduction of cells. |
|
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Term
|
Definition
| The disruption of a cell and separation of its organelles by centrifugation. |
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Term
|
Definition
|
|
Term
|
Definition
| A double membrane across the midline of a dividing plant cell, between which the new cell wall forms during cytokinesis. |
|
|
Term
|
Definition
| A protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists. In plant cells, the wall is formed of cellulose fibers embedded in a polysaccharide-protein matrix. The primary cell wall is thin and flexible, whereas the secondary cell wall is stronger and more rigid and is the primary constituent of wood. |
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Term
|
Definition
| The type of immunity that functions in defense against fungi, protists, bacteria, and viruses inside host cells and against tissue transplants, with highly specialized cells that circulate in the blood and lymphoid tissue. |
|
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Term
|
Definition
| The structural and functional divergence of cells as they become specialized during a multicellular organism's development; dependent on the control of gene expression. |
|
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Term
|
Definition
| The most prevalent and efficient catabolic pathway for the production of ATP, in which oxygen is consumed as a reactant along with the organic fuel. |
|
|
Term
|
Definition
| A type of protist that has unicellular amoeboid cells and multicellular reproductive bodies in its life cycle. |
|
|
Term
|
Definition
| A structural polysaccharide of cell walls, consisting of glucose monomers joined by B-1, 4-glycosidic linkages. |
|
|
Term
|
Definition
| A temperature scale (degC) equal to 5/9 (degF-32) that measures the freezing point of water at 0degC and the boiling point of water at 100degC. |
|
|
Term
|
Definition
| The narrow cavity in the center of the spinal cord that is continuous with the fluid-filled ventricles to the brain. |
|
|
Term
| central nervous system (CNS) |
|
Definition
| In vertebrate animals, the brain and spinal cord. |
|
|
Term
|
Definition
| A membranous sac in a mature plant cell with diverse roles in reproduction, growth, and development. |
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|
Term
|
Definition
| A structure in an animal cell composed of cylinders of microtubule triplets arranged in a 9+0 pattern. An animal cell usually has a pair of centrioles involved in cell division. |
|
|
Term
|
Definition
| The centralized region joining two sister chromatids. |
|
|
Term
|
Definition
| Material present in the cytoplasm of all eukaryotic cells, important during cell division; the microtubule-organizing center. |
|
|
Term
|
Definition
| An evolutionary trend toward the concentration of sensory equiptment on the anterior end of the body. |
|
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Term
|
Definition
| A chordate without a backbone, represented by lancelets, tiny marine animals. |
|
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Term
|
Definition
| Part of the vertebrate hindbrain (rhombencephalon) located dorsally; functions in unconscious coordination of movement and balance. |
|
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Term
|
Definition
| The surface of the cerebrum; the largest and most complex part of the mammalian brain, containing sensory and motor nerve cell bodies of the cerebrum; the part of the vertebrate brain most changed through evolution. |
|
|
Term
|
Definition
| The right or left side of the vertebrate brain. |
|
|
Term
|
Definition
| Bloodderived fluid that surrounds, protects, against infection, nourishes, and cushions the brain and spinal cord. |
|
|
Term
|
Definition
| The dorsal portion, composed of right and left hemispheres, of the vertebrate forebrain; the integrating center for memory, learning, emotions, and other highly complex functions of the central nervous system. |
|
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Term
|
Definition
| The neck of the uterus, which opens into the vagina. |
|
|
Term
|
Definition
| A scrubland biome of dense, spiny evergreen shrubs found at midlatitudes along coasts where cold ocean currents circulate offshore; characterized by mild, rainy winters and long, hot, dry summers. |
|
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Term
|
Definition
| The neck of the uterus, which opens into the vagina. |
|
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Term
|
Definition
| Protein molecules that assist the proper folding of other proteins. |
|
|
Term
|
Definition
|
|
Term
|
Definition
| The green algal group that shares two ultrastructural features with land plants. They are considered to be the closest relatives of land plants. |
|
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Term
|
Definition
| Clawlikefeeding appendages characteristic of the chelicerate group. |
|
|
Term
|
Definition
| The animal phylum that includes horseshoe crabs, scorpions, ticks, spiders, and an extinct group called the eurypterids. |
|
|
Term
|
Definition
| Members of the animal phylum that includes horseshoe crabs, scorpions, ticks, spiders, and an extinct group called the eurypterids. |
|
|
Term
|
Definition
| An attraction between two atoms resulting from a sharing of outer-shell electrons or the presence of opposite charges on the atoms; the bonded atoms gain complete outer electron shells. |
|
|
Term
|
Definition
| Energy stored in the chemical bonds of molecules; a form of potential energy. |
|
|
Term
|
Definition
| In a reversible chemical reaction, the point at which the rate of the forward reaction equals the rate of the reverse reaction. |
|
|
Term
|
Definition
| A process leading to chemical changes in matter; involves the making and/or breaking of chemical bonds. |
|
|
Term
| chemically-gated ion channels |
|
Definition
| Specialized ion channels that open or close in response to a chemical stimulus. |
|
|
Term
|
Definition
| An energycoupling mechanism that uses energy stored in the form of a hydrogen ion gradient across a membrane to drive cellular work, such as the synthesis of ATP. Most ATP synthesis in cells occurs by chemiosmosis. |
|
|
Term
|
Definition
| An organism that needs only carbon dioxide as a carbon source but that obtains energy by oxidizing inorganic substances. |
|
|
Term
|
Definition
| An organism that must consume organic molecules for both energy and carbon. |
|
|
Term
|
Definition
| A group of about 50 different proteins secreted by blood vessel endothelial cells and monocytes. These molecules bind to receptors on many types of leukocytes and induce numerous changes central to inflammation. |
|
|
Term
|
Definition
| A receptor that transmits information about the total solute concentration in a solution or about individual kinds of molecules. |
|
|
Term
| chiasma (plural, chiasmata) |
|
Definition
| The X-shaped, microscopically visible region representing homologous chromatids that have exchanged geneteic material through crossing over during meiosis. |
|
|
Term
|
Definition
| The animal class that includes centipedes. |
|
|
Term
|
Definition
| A structural polysaccharide of an amino sugar found in many fungi and in the exoskeleton of all arthropods. |
|
|
Term
|
Definition
| A green pigment located within the chloroplasts of plants. Chlorophyll a can participate directly in the light reactions, which convert solar energy to chemical energy. |
|
|
Term
|
Definition
| A type of blue-green photosynthetic pigment that participates directly in the light reactions. |
|
|
Term
|
Definition
| A type of yellow-green accessory photosynthetic pigment that transfers energy to chlorophyll a. |
|
|
Term
|
Definition
| An organelle found only in plants and photosynthetic protists that absorbs sunlight and uses it to drive the synthesis of organic compounds from carbon dioxide and water. |
|
|
Term
|
Definition
| A flagellated feeding cell found in sponges. Also called a collar cell, it has a collarlike ring that traps food particles around the base of its flagellum. |
|
|
Term
|
Definition
| A hormone released from the walls of the duodenum in response to the presence of amino acids or fatty acids. |
|
|
Term
|
Definition
| A steroid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steriods. |
|
|
Term
|
Definition
| The vertebrate class of cartilaginous fishes, represented by sharks and their relatives. |
|
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Term
|
Definition
| A protein-carbohydrate complex secreted by chondrocytes; chondrin and collagen fibers form cartilage. |
|
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Term
|
Definition
|
|
Term
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Definition
| A member of a diverse phylum of animals that possess a notochord; a dorsal, hollow nerve cord; pharyngeal gill slits; and a postanal tail as an embryo. |
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Term
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Definition
| The outermost of four extraembryonic membranes; contributes to the formation of the mammalian placenta. |
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Term
| chorionic villus sampling (CVS) |
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Definition
| A technique for diagnosing genetic and congenital defects in a fetus by removing and analyzing a small sample of the fetal portion of the placenta. |
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Term
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Definition
| A thin, pigmented inner layer of the vertebrate eye. |
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Term
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Definition
| The complex of DNA and proteins that make up a eukaryotic chromosome. When the cell is not dividing, chromatin exists as a mass of very long, thin fibers that are not visible with a light microscope. |
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Definition
| In some classification systems, a kingdom consisting of brown algae, golden algae, and diatoms. |
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Term
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Definition
| A threadlike, genecarrying structure found in the nucleus. Each chromosome consists of one very long DNA molecule and associated proteins. See chromatin. |
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Term
| chromosome theory of inheritance |
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Definition
| A basic principle in biology stating that genes are located on chromosomes and that the behavior of chromosomes during meiosis accounts for inheritance patterns. |
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Term
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Definition
| A DNA mapping technique that begins with a gene or other sequence that has already been cloned, mapped, and sequenced and "walks" along the chromosomal DNA from that locus, producing a map of overlapping restriction fragments. |
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Term
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Definition
| Small intracellular globules composed of fats that are mixed with cholesterol and coated with special proteins. |
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Term
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Definition
| An enzyme found in the duodenum. It is specific for peptide bonds adjacent to certain amino acids. |
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Term
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Definition
| Mainly aquatic primitive fungi that form uniflagellated spores (zoospores). The chytrids and fungi are now thought to form a monophyletic branch of the eukaryotic tree. |
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Term
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Definition
| A portion of the vertebrate eye associated with the lens. It produces the clear, watery aqueous humor that fills the anterior cavity of the eye. |
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Term
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Definition
| A type of protozoan that moves by means of cilia. |
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Term
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Definition
| A short cellular appendage specialized for locomotion, formed from a core of nine outer doublet microtubules and two inner single microtubules ensheathed in an extension of plasma membrane. |
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Term
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Definition
| A physiological cycle of about 24 hours that is present in all eukaryotic organisms and that persists even in the absence of external cues. |
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Term
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Definition
| Each evolutionary branch in a cladogram. |
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Term
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Definition
| A taxonomic approach that classifies organisms according to the order in time at which branches arise along a phylogenetic tree, without considering the degree of morphological divergence. |
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Term
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Definition
| A pattern of evolutionary change that produces biological diversity by budding on or more new species from a parent species that continues to exist; also called branching evolution. |
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Term
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Definition
| A dichotomous phylogenetic tree that branches repeatedly, suggesting a classification of organisms based on the time sequence in which evolutionary branches arise. |
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Term
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Definition
| In classification, the taxonomic category above order. |
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Term
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Definition
| The animal group that includes scorpions, spiders, ticks, and mites. |
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Term
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Definition
| The centipede group of animals. |
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Term
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Definition
| The millipede group of animals. |
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Term
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Definition
| A collection of cell surface glycoproteins encoded by a family of genes called the major histocompatibility complex. In humans, these glycoproteins are also known as the HLA, human leukocyte antigens. Class I MHC molecules are found on all nucleated cells. |
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Term
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Definition
| A collection of cell surface glycoproteins encoded by a family of genes called the major histocompatibility complex. In humans, these glycoproteins are also known as the HLA, human leukocyte antigens. Class II MHC molecules are restricted to a few specialized cell types. |
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Term
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Definition
| A type of associative learning; the association of a normally irrelevant stimulus with a fixed behavioral response. |
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Term
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Definition
| The process of cytokinesis in animal cells, characterized by pinching of the plasma membrane; specifically, the succession of rapid cell divisions without growth during early embryonic development that converts the zygote into a ball of cells. |
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Term
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Definition
| The first sign of cleavage in an animal cell; a shallow groove in the cell surface near the old metaphase plate. |
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Term
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Definition
| The prevailing weather conditions at a locality. |
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Term
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Definition
| Graded variation in some traits of individuals that parallels a gradient in the environment. |
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Term
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Definition
| An organ in the female that engorges with blood and becomes erect during sexual arousal. |
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Term
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Definition
| A common opening for the digestive, urinary, and reproductive tracts in all vertebrates except most mammals. |
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Term
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Definition
| The mechanism that determines specificity and account for antigen memory in the immune system; occurs because an antigen introduced into the body selectively activates only a tiny fraction of inactive lymphocytes, which proliferate to form a clone of effector cells specific for the stimulating antigen. |
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Term
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Definition
| (1) A lineage of genetically identical individuals or cells. (2) In popular usage, a single individual organism that is genetically identical to another individual. (3) As a verb, to make one or more genetic replicas of an individual or cell. See also gene cloning. |
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Term
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Definition
| Using a somatic cell from a multicellular organism to make one or more genetically identical individuals. |
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Term
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Definition
| An agent used to transfer DNA in genetic engineering. A plasmid that moves recombinant DNA from a test tube back into a cell is an example of a cloning vector, as is a virus that transfers recombinant DNA by infection. |
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Term
| closed circulatory system |
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Definition
| Circulatory systems in which blood is confined to vessels and is kept separate from the interstitial fluid. |
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Term
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Definition
| The common name for members of the phylum Basidiomycota. The name comes from the clublike shape of the basidium. |
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Term
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Definition
| Describing a dispersion pattern in which individuals are aggregate in patches. |
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Term
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Definition
| A specialized cell for which the phylum Cnidaria is named; consists of a capsule containing a fine coiled thread, which, when discharged, functions in defense and prey capture. |
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Term
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Definition
| The complex, coiled organ of hearing that contains the organ of Corti. |
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Term
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Definition
| A phenotypic situation in which the two alleles affect the phenotype in separate, distinguishable ways. |
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Term
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Definition
| A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code. |
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Term
| coefficient of relatedness |
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Definition
| The probability that a particular gene present in on individual will also be in herited from a common parent or ancestor in a second individual. |
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Term
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Definition
| A body cavity completely lined with mesoderm. |
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Term
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Definition
| An animal whose body cavity is completely lined by mesoderm, the layers of which connect dorsally and ventrally to form mesenteries. |
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Term
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Definition
| Referring to a multinucleated condition resulting from the repeated division of nuclei without cytoplasmic division. |
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Term
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Definition
| An organic molecule serving as a cofactor. Most vitamins function as coenzymes in important metabolic reactions. |
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Term
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Definition
| The mutual influence on the evolution of two different species interacting with each other and reciprocally influencing each other's adaptations. |
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Term
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Definition
| Any nonprotein molecule or ion that is required for the proper functioning of an enzyme. Cofactors can be permanently bound to an active site or may bind loosely with the substrate during catalysis. |
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Term
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Definition
| The ability of an animal's nervous system to perceive, store, process, and use information obtained by its sensory receptors. |
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Term
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Definition
| The scientific study of cognition; the study of the connection between data processing by nervous systems and animal behavior. |
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Term
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Definition
| A representation within the nervous system of spatial relations among objects in an animal's environment. |
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Term
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Definition
| The binding together of like molecules, often by hydrogen bonds. |
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Term
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Definition
| The idea that specific evolutionary adaptations and discrete complexes of genes define species. |
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Term
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Definition
| A group of individuals of the same age, from birth until all are dead. |
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Term
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Definition
| The insertion of a penis into a vagina, also called sexual intercourse. |
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Term
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Definition
| The covering of the young root of the embryo of a grass seed. |
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Term
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Definition
| A glycoprotein in the extracellular matrix of animal cells that forms strong fibers, found extensively in connective tissue and bone; the most abundant protein in the animal kingdom. |
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Term
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Definition
| Tough fibers of the extracellular matrix. They are made of collagen that are nonelastic and do not tear easily when pulled lengthwise. |
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Term
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Definition
| The location in the kidney where filtrate from renal tubules is collected; the filtrate is now called urine. |
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Term
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Definition
| A flexible plant cell type that occurs in strands or cylinders that support young parts of the plant without restraining growth. |
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Term
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Definition
| Adhesive structures on the tentacles of ctenophores. |
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Term
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Definition
| The tubular portion of the vertebrate alimentary tract between the small intestine and the anus; functions mainly in water absorption and the formation of feces. |
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Term
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Definition
| The column shape of one type of epithelial cell. |
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Term
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Definition
| A symbiotic relationship in which the symbiont benefits but the host is neither helped nor harmed. |
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Term
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Definition
| All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction. |
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Term
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Definition
| The study of how interactions between species affect community structure and organization. |
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Term
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Definition
| A type of plant cell that is connected to a sieve-tube cell by many plasmodesmata and whose nucleus and ribosomes may serve one or more adjacent sieve-tube cells. |
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Term
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Definition
| A substance that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics. |
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Term
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Definition
| A set of about 20 serum proteins that carry out a cascade of steps leading to the lysis of microbes. |
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Term
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Definition
| An immune response in which antigen-antibody complexes activate complement proteins. |
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Term
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Definition
| A group of at least 20 blood proteins that cooperate with other defense mechanisms; may amplify the inflammatory response, enhance phagocytosis, or directly lyse pathogens; activated by the onset of the immune response or by surface antigens on microorganisms or other foreign cells. |
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Term
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Definition
| A DNA molecule made in vitro using mRNA as a template and the enzyme reverse transcriptase, A cDNA molecule therefore corresponds to a gene, but lacks the introns present in the DNA of the genome. |
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Term
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Definition
| A digestive tube that runs between a mouth and an anus; also called alimentary canal. An incomplete disgestive tract has only one opening. |
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Term
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Definition
| A type of inheritance in which the phenotypes of the heterozygote and dominant homozygote are indistinguishable. |
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Term
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Definition
| A flower that has sepals, petals, stamens, and carpels. |
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Term
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Definition
| The transformation of a larva into an an adult that looks very different, and often functions very differently in its environment, than the larva. |
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Term
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Definition
| A substance consisting of two or more elements in a fixed ratio. |
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Term
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Definition
| A type of multifaceted eye in insects and crustaceans consisting of up to several thousand light-detecting, focusing ommatidia; especially good at detecting movement. |
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Term
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Definition
| A small molecule that cooperates with a repressor protein to switch an operon off. |
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Term
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Definition
| An increase or decrease in the density of a chemical substance in an area. Cells often maintain concentration gradients of ions across their membranes. When a gradient exists, the ions or other chemical substances involved tend to move from where tehy are more concentrated to where they are less concentrated. |
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Term
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Definition
| The fertilization of the egg by a sperm cell. |
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Term
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Definition
| A reaction in which two molecules become covalently bonded to each other through the loss of a small molecule, usually water; also called dehydration reaction. |
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Term
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Definition
| The direct transfer of thermal motion (heat) between molecules of objects in direct contact with each other. |
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Term
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Definition
| One of two types of photoreceptors in the vertebrate eye; detects color during the day. |
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Term
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Definition
| A characterization of an animal in regard to environmental variables. The animal is a conformer if it allows some conditions within its body to vary with certain external changes. |
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Term
| conidium (plural, conidia) |
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Definition
| A naked, asexual spore produced at the ends of hyphae in ascomycetes. |
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Term
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Definition
| A gymnosperm whose reproductive structure is the cone. Conifers include pines, firs, redwoods, and other large trees. |
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Term
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Definition
| The largest of the four gymnosperm phyla, the reproductive structure is the cone. Conifers include pines, firs, redwoods, and other large trees. |
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Term
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Definition
| In bacteria, the direct transfer of DNA between two cells that are temporarily joined. |
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Term
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Definition
| A mucous membrane that helps keep the eye moist; lines the inner surface of the eyelid and covers the front of the eyeball, except the cornea. |
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Term
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Definition
| Animal tissue that functions mainlyto bind and support other tissues, having a sparse population of cells scattered through an extracellular matrix. |
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Term
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Definition
| The group of ancient vertebrates that date back as far as 510 million years. |
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Term
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Definition
| A goal-oriented science that seeks to counter biodiversity crisis, the current rapid decrease in Earth's variety of life. |
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Term
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Definition
| The prevention of pregnancy. |
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Term
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Definition
| A membranous sac that helps move excess water out of the cell. |
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Term
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Definition
| Segments of noncoding DNA that help regulate transcription of a gene by binding proteins called transcription factors. |
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Term
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Definition
| The mass movement of warmed air or liquid to or from the surface of a body or object. |
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Term
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Definition
| The independent development of similarity between species as a result of their having similar ecological roles and selection pressures. |
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Term
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Definition
| A mechanism of cell crawling in which the cells of a tissue layer rearrange themselves in such a way that the sheet of cells becomes narrower while it becomes longer. |
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Term
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Definition
| An interaction of the constituent subunits of a protein whereby a conformational change in one subunit is transmitted to all the others. |
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Term
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Definition
| A group of small crustaceans that are importan members of marine and freshwater planktom communitites. |
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Term
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Definition
| Warm water, tropical, ecosystems dominated by the hard skeletal structures secreted primarily by the resident cnidarians. |
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Term
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Definition
| A cylinder of meristematic tissue in plants that produces cork cells to replace the epidermis during secondary growth. |
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Term
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Definition
| The transparent frontal protion of the sclera, which admits light into the vertebrate eye. |
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Term
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Definition
| The thick band of nerve fibers that connect the right and left cerebral hemispheres in placental mammals, enabling the hemispheres to process information together. |
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Term
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Definition
| A secreting tissue in the ovary that forms from the collapsed follicle after ovulation and produces progesterone. |
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Term
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Definition
| Ground tissue that is between the vascular and dermal tissue in a root or dicot stem. |
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Term
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Definition
| Vesicles that begin just under the egg plasma membrane prior to their involvement in the cortical reaction. |
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Term
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Definition
| Nephrons located almost entirely in the renal cortex. These nephrons have a reduced loop of Henle. |
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Term
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Definition
| A series of changes in the cortex of the egg cytoplasm during fertilization. |
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Term
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Definition
| A family of steroids synthesized by and released from the adrenal cortex. |
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Term
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Definition
| The coupling of the "downhill" diffusion of one substance to the "uphill" transport of another against its own concentration gradient. |
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Term
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Definition
| The one (monocot) or two (dicot) seed leaves of an agiosperm embryo. |
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Term
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Definition
| The opposite flow of adjacent fluids that maximizes transfer rates; for example, blood in the gills flows in the opposite direction in which water passes of the gills, maximizing oxygen uptake and carbon dioxide loss. |
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Term
| countercurrent heat exchanger |
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Definition
| A s[ecoa; arrangement of blood vessels that helps trap heat in the body core and is important in reducing heat loss in many endotherms. |
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Term
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Definition
| Behavior patterns that lead up to copulation or gamete release. |
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Term
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Definition
| A type of strong chemical bond in which two atoms share one pair of valence electrons. |
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Term
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Definition
| Nerves that leave the brain and innervate organs of the head and upper body. |
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Term
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Definition
| The chordate subgroup that possess a cranium. |
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Term
| crassulacean acid metabolism (CAM) |
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Definition
| A type of metabolism in which carbon dioxide is taken in at night and incorporated into a variety of organic acids. |
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Term
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Definition
| An infolding of the inner membrane of a mitochondrion that houses the electron trapnsport chain and the enzyme catalyzing the synthesis of ATP. |
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Term
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Definition
| The reptile group that includes crocodiles and alligators. |
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Term
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Definition
| The reciprocal exchange of genetic material between nonsister chromatids during synapsis of meiosis I. |
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Term
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Definition
| The transfer of pollen from flowers of one plant to flowers of another plant of the same species. |
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Term
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Definition
| The animal phylum that includes mostly aquatic animals such as crabs, lobsters, crayfish, and shrimp. |
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Term
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Definition
| A member of a major arthropod phylum that includes lobsters, crayfish, crabs, shrimps, and barnacles. |
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Term
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Definition
| Camouflage, making potential prey difficult to spot against its background. |
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Term
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Definition
| The cubic shape of a type of epithelial cell. |
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Term
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Definition
(1) A waxy covering on the surface of stems and leaves that acts as an adaptation to prevent desication in terrestial plants.
(2) The exoskeleton of an arthropod, consisting of layers of protein and chitin that are variously modified for different functions. |
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Term
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Definition
| Photosynthetic, oxygen-producing bacteria (formerly known as blue-green algae). |
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Term
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Definition
| A phylum of gymnosperms that superficially resemble palms. Cycads bear naked seeds on sporophylls, leaves specialized for reproduction. |
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Term
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Definition
| Cyclic adenosine monophosphate, a ring-shaped molecule made from ATP that is a common intracellular signaling molecule (second messenger) in eukaryotic cells (for example, in vertebrate endocrine cells). It is also a regulator of some bacterial operons. |
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Term
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Definition
| A route of electron flow during the light reactions of photosynthesis that involves only photosystem 1 and that produces ATP but not NADPH or oxygen. |
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Term
| cyclic photophosphorylation |
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Definition
| The generation of ATP by cyclic electron flow. |
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Term
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Definition
| A regulatory protein whose concentration fluctuates cyclically. |
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Term
| cyclin-dependent kinase (Cdk) |
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Definition
| A protein kinase that is active only when attached to a particular cyclin. |
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Term
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Definition
| A genetic disorder that occurs in people with two copies of a certain recessive allele; characterized by an excessive secretion of mucus and consequent vulnerability to infection; fatal if untreated. |
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Term
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Definition
| An iron-containing protein, a component of electron transport chains in mitochondria and chloroplasts. |
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Term
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Definition
| In the vertebrate immune system, protein factors secreted bu macrophages and helper T cells as regulators of neighboring cells. |
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Term
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Definition
| The division of the cytoplasm to form two separate daughter cells immediately after mitosis. |
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Term
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Definition
| A class of related plant hormones that retard aging and act in concert with auxins to stimulate cell division, influence the pathway of differentation, and control apical dominance. |
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Term
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Definition
| Charts of chromosomes that locate genes with respect to chromosomal features. |
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Term
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Definition
| The entire contents of the cell, exclusive of the nucleus, and bounded by the plasma membrane. |
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Term
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Definition
| The maternal substances in the egg that influences the course of early development by regulating the expression of genes that affect the developmental fate of cells. |
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Term
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Definition
| A circular flow of cytoplasm, involving myosin and actin filaments, that speeds the distribution of materials within cells. |
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Term
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Definition
| A network of microtubules, microfilaments, and intermediate filaments that branch throughout the cytoplasm and serve a variety of mechanical and transport functions. |
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Term
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Definition
| The semifluid portion of the cytoplasm. |
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Term
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Definition
| A type of lymphocyte that kills infected cells and cancer cells. |
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Term
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Definition
| A daily decrease in metabolic activity and corresponding body temperatures during times of inactivity for some small mammals and birds. The physiological changes during resting periods enable these organisms to survive on energy stores in their tissues. |
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Term
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Definition
| A measure of mass for atoms and subatomic particles. |
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