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Bio 1306 Final Exam- old stuff
vocabulary terms and key concepts- old stuff
165
Biology
Undergraduate 1
05/01/2011

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Term
Biology
Definition
the scientific study of living things
Term
Evolution
Definition
change in the genetic makeup of biological populations through time
Term
Natural Selection
Definition
differential survival and reproduction among individuals in a population based on variation in their traits
Term
Species
Definition
a group of organisms that can produce viable and fertile offspring with one another
Term
Population
Definition
a group of individuals of a single species that live and interbreed in a particular geographic area at the same time
Term
Adaptation
Definition
two meanings; refers to both the processes by which characteristics that appear to be useful to their bearers evolve and to the characteristics themselves
Term
Difference between allele frequencies and genotypic frequencies
Definition
allele frequencies measure the amount of genetic variation in a population; genotype frequencies show how a population's genetic variation is distributed among its members
Term
Neutral Allele
Definition
an allele that does not affect the fitness of an organism
neutral alleles are unaffected by natural selection
Term
4 key points for evidence of evolution
Definition
Mutation- any change in the nucleotide sequences of an organism's DNA. ultimate source of variation
Gene flow- migration of individuals and movements of gametes between populations. magnitude of effect is related to extent of differences between populations.
Genetic Drift- random changes in allele frequencies from one generation to the next. founder effect, bottleneck effect.
Natural Selection- differential survival and reproduction among individuals in a population based on variation in traits.
Term
Allele Frequency
Definition
the number of copies of the allele in the population divided by the sum of alleles in the population.
Term
Genotype Frequency
Definition
the number of individuals that have a given genotype divided by the total number of individuals in the population
Term
Hardy-Weinberg Equilibrium
Definition
a principle in which allele frequencies do not change across generations and genotype frequencies can be predicted from allele frequencies
Term
The conditions that must be met for a population to stay at Hardy-Weinberg equilibrium
Definition
1. Mating is random
2. Population size is infinite
3. There is no gene flow
4. There is no mutation
5. Selection does not affect the survival of particular genotypes
Term
Fitness
Definition
in regards to a phenotype, it is the the reproductive contribution of a phenotype to subsequent generations relative to the contributions of other phenotypes
Term
Stabilizing Selection
Definition
preserves the average characteristics of a population by favoring average individuals
Term
Directional Selection
Definition
changes the characteristics of a population by favoring individuals that vary in one direction from the mean of the population
Term
Disruptive Selection
Definition
changes the characteristics of a population by favoring individuals that vary in both directions from the mean of the population
Term
Allopatric Speciation
Definition
speciation that results when a population is divided by a physical barrier
Term
Sympatric Speciation
Definition
the partition of a gene pool without physical isolation
Term
Microevoulution
Definition
change in gene frequency
Term
Fossils
Definition
the preserved remains of ancient organisms
Term
Methods of dating fossils
Definition
using the half-life of radioactive isotopes; studying sedimentary rocks; radioisotope dating of rocks combined with fossil analysis; paleomagnetic dating
Term
Early events in the history of Earth
Definition
Earth formed- 4.5 bya
Bacteria present- 3.5 bya
Eukaryotic cells present- 1.5 bya
Term
Cambrian Explosion
Definition
oxygen levels approached its current levels and land masses came together, making good conditions for an explosion of life forms. happened over millions of years. life diversified in periods after
Term
Pangaea
Definition
the continents coalesced completely to form this supercontinent in the Permian period
Term
Laurasia and Gondwana
Definition
during the Jurassic period, Pangaea was fully divided into these two parts. One drifted north and one south
Term
angiosperm sexual reproduction
Definition
occurs in the flower; involves mitosis and meiosis, and the alteration of generations
Term
4 groups of a flower from inside out
Definition
carpels; stamens; petals; sepals
Term
alteration of generations
Definition
the alteration between haploid and diploid nuclei
Term
monoecious
Definition
bear both male and female parts. in other words, hermaphroditic
Term
dioecious
Definition
bear either male-only or female-only parts (flowers)
Term
double fertilization
Definition
there are two nuclear fusion events; one sperm fuses with the egg cell nucleus, the other sperm fuses with the two polar nuclei
Term
Adaptations in plants related to terrestrial life
Definition
shift of importance from gametophyte to sporophyte; increased protection of developing sporophyte
Term
two general groups of seed plants
Definition
gymnosperms- pine trees and relatives, angiosperms- flowering plants; all have reduced gametophyte, go through meiosis to produce spores, mitosis to produce gametes
Term
angiosperm gametophyte/sporophyte
Definition
the embryo sac (where the male and female nuclei meet and fuse) is the female gametophyte (n), the pollen grain is the male gametophyte (n). the flower is the mature sporophyte (2n)
Term
Short Day Plants
Definition
flower only when the day is shorter than a critical minimum
in other words, long night plants. they flower when the night is longer than the critical night length of nine hours
Term
Long-day Plants
Definition
flower only when the day is longer than a critical minimum.
in other words, are short night plants. they flower when the night is shorter than the critical night length of nine hours
Term
Advantages of asexual reproduction
Definition
it eliminates genetic recombination, so if a plant is well adapted to its environment, asexual reproduction allows it to pass on to all its progeny a superior combination of alleles.
Term
Disadvantages of asexual reproduction
Definition
a change in the environment can leave an asexually reproducing species at a disadvantage because the population will lack the genetic diversity it needs for the population to survive (from a disease, etc)
Term
Sexual reproduction in animals in 3 fundamental steps
Definition
Gametogenesis: making gametes (haploid cells)
Mating: bringing gametes together
Fertilization: fusing gametes
Term
Spermatogenesis
Definition
a process by which spermatogonium (2n) are generated into sperm cells (n). spermatogonium (2n)-> primary spermatocyte (2n)-> 2 secondary spermatocytes (n)- first meiotic division -> 4 spermatids (n)- second meiotic division, still connected by cytoplasmic crossbridges -> 4 sperm cells (n).
Term
Oogenesis
Definition
process by which oogonium (2n) becomes a mature ovum (n). the oogonium goes through mitosis to form the primary oocyte (2n) which usually wont divide meiotically until puberty. the first meiotic division produces the secondary oocyte (n), and an uneven distribution of cytoplasm makes a polar body. the second meiotic division produces the ootid (n), and a second polar body. the ootid becomes the mature ovum (egg)(n) and the two polar bodies degenerate.
Term
Acrosomal Reaction
Definition
the acrosome is the membrane-enclosed structure at the front of the sperm head and the acrosomal reaction is how it penetrates the female egg. It begins with plasma membrane covering the sperm head breaking down and the acrosomal process forming. this, combined with other enzymes and proteins, penetrates the egg's membrane and allows the "fertilization cone" to enter the egg.
Term
Fertilization
Definition
the union of the haploid sperm and haploid egg, which creates a diploid zygote.
two types- external and internal. external fertilization allows animals to release their gametes into the water. internal fertilization requires the release of sperm into the female reproductive tract
Term
Development
Definition
the steps taken by a zygote in order to become a multicellular animal.
involves 3 processes: cell division/growth, cell differentiation, morphogenesis
Term
Morphogenesis
Definition
the development of form (3 germ layers- endoderm, ectoderm, mesoderm); the overall consequence of determination, differentiation, and growth
Term
Cleavage
Definition
a rapid series of cell divisions that result in the transformation of the diploid zygote into a mass of cells. it is "the recovery of multicellularity" and "cell division without growth"
Term
Blastocoel
Definition
in the process of cleavage in most animals, rapid DNA replication and mitosis with no cell growth result in an embryo becoming a solid ball of smaller and smaller cells. the central fluid-filled cavity is the ____________
Term
Blastula
Definition
what the embryo is called after much cleavage forms a blastocoel. the individual cells of this formation are called blastomeres.
Term
Gastrulation
Definition
the process whereby the tissues are put into proper orientations; mostly a process of migration
Term
the three germ layers that form during gastrulation (morphogenesis)
Definition
endoderm- innermost layer; lining of digestive/respiratory tract, pancreas, and liver (gut).
ectoderm- outermost layer; gives rise nervous system, skin, mouth
mesoderm- middle layer; gives rise to many organs including heart, muscles, and bones
Term
Cleavage patterns (they are related to yolk amount and distribution)
Definition
microlecithal (homolecithal) eggs have holoblastic, equal cleavage.
mesolecithal eggs have holoblastic, unequal cleavage.
megalecithal eggs have discoblastic cleavage
Term
Neurulation
Definition
the initiation of the nervous system; one of the earlier processes of organogenesis- the phase of "development" when many organs and organ systems develop simultaneously and in coordination with one another
Term
Notochord
Definition
formed by a group of cells that extend down the center of the embryo; it gives structural support to the developing embryo and is eventually replaced by the vertebral column. it also makes the spherical embryo long
Term
Baer's Law
Definition
says the more closely two animals are related, the more similar their developmental patterns are. Also, primitive structures develop early and advanced structures develop later
Term
Biogenetic Law
Definition

ontogeny recapitulates phylogeny

meaning that the way the embryo develops relates to the way that its ancesters developed from embryo to maturity

Term
homologous structures
Definition
have the same origin but different functions
Term
analogous structures
Definition
have a different origin but the same function
Term
Process of neurulation
Definition
it is the formation of an internal neural tube from an external sheet of cells. the first sign is the formation of the neural plate. the edges of the neural plate thicken to form "neural folds". between the neural folds is the "neural groove", which deepens as the folds roll over it converging to the midline. the folds fuse, forming the neural tube.
Term
extraembryonic membranes
Definition

membranes that originate from the embryo but are not actually part of it. 

the yolk sac provides nutrients to the embryo

the allantois functions to store the excreted matter of the embryo

the amnion is the protective covering of the embryo

the chorion is the protective membrane covering the yolk sac, embryo, allantois, and amnion

in mammals, extraembryonic membranes interact with tissues of the mother to form the placenta

Term
Inbibition
Definition
the uptake of water; the first step in seed germination
Term
Germination
Definition
the process of a seed breaking dormancy and developing into a seedling; it is completed when the radicle (embryonic root) emerges from the seed coat, when the plant is then called a seedling
Term
Gibberellins
Definition
plant hormones that produces a growth-promoting chemical substance. released by the embryo
Term
aluerone layer
Definition
the layer that underlies the seed coat
Term
Auxin
Definition
a growth regulator that controls the pattern of growth by stimulating growth; it stimulates cell elongation. it is produced in the tips but migrates somewhere in the center.
Term
Cytokinins
Definition
operates opposite but in conjunction with auxin to regulate plant growth. can work in the dark, because it is produced in the roots and travels to tips
Term
Phytocrome red and phytocrome far-red
Definition
phytocrome (a blue pigment) measures the length of day. phytocrome red absorbs red light and become phytocrome far-red. this form prefers far-red light, and when it does so it is converted back to phytocrome red. if there is a lot of red light, the day was long. a lot of far-red light means a long night.
Term
Mineral Nutrients
Definition
nutrients obtained from the soil, which many plants need. Include calcium, phosphorus, sulfur (needed for amino acid formation), iron (needed for pigment formation)
Term
Essential elements
Definition
a nutrient is called this if its absence causes severe disruption of normal plant growth and reproduction.
Term
heterotrophs
Definition
derive their nutrition from eating other organisms.
Term
autotrophs
Definition
can use solar energy or inorganic chemical energy to synthesize all of their components.
they are the source of organic material for heterotrophs.
Term
major requirements for animal nutrition
Definition
a source of carbohydrates (most important), glycerol, fatty acids, lipids, amino acids, proteins, nucleotides, and nucleic acids
Term
Macronutrients
Definition
elements required in large amounts (more than 100 mg/day)
Term
Micronutrients
Definition
elements required in tiny amounts (less than 100 mg/day)
Term
Vitamins
Definition
like essential amino acids and fatty acids, these are carbon compounds that an animal requires for growth and metabolism but cannot synthesize for itself.
Term
Water-soluble vitamins
Definition
includes B12 and C; polar, dissolve well in water
Term
Fat-soluble vitamins
Definition
includes A, D, E, and K; non-polar, don't dissolve well in water
Term
Tubular Gut
Definition
*an opening at each end; the buccal cavity is specialized for preparation of food, gizzard is specialized sac for furthur grinding, stomach or crop serves for food storage, intestine empties out into the anus. sphinctors are responsible for control of passage between regions
Term
Layers of the Gut
Definition
mucosa, submucosa, muscularis externa, serosa. (innermost -> outermost)
Term
Ruminant stomach
Definition
"cud chewers". this stomach has four chambers; the rumen, reticulum, omasum, and abomasum.
Term
Immune System
Definition
the defense of the body against invasion, infection, and/or change.
Term
Functions of the Immune System
Definition
recognizes a threat, eliminates that threat, then remembers that threat for future reference
Term
Blood Plasma
Definition
a yellowish solution containing ions, small molecular solutes, and soluble proteins. suspended in it are red blood cells, white blood cells, and platelets.
Term
Lymph
Definition
a fluid derived from the blood and other tissues that acumulates in intercellular spaces throughout the body
Term
Leukocytes
Definition
also called white blood cells; they are larger than red blood cells, nucleated, capable of independent movement in bloodstream, and its levels change in relation to infection. two types: phagocytes and lymphocytes
Term
B Cells
Definition
part of the humoral immune response, these cells bind free antigen to its antibody receptors. it secretes antibodies and has specific antibody receptors on its surface
Term
T Cells
Definition
part of the cellular immune response, these cells kill all cells with exposed antigen on their surface
Term
Antibodies
Definition
proteins that bind specifically to certain substances in order to inactivate viruses and toxins. produced by B cells
Term
effector cells
Definition
leukocytes that carry out the attack on the antigen.
Term
memory cells
Definition
long-lived cells that retain the ability to start dividing on short notice to produce more effector and more memory cells
Term
Fick's law
Definition
says that a respiratory surface of a unicellular organism must have 1. a large surface area, 2. a thin permeable surface, 3. a moist exchange surface
Term
Gas Exchange
Definition
the exchange of O2 and CO2 on a respiratory surface (in mammals it is the alveoli). it requires a wet membrane. gas exchange systems are made up of gas exchange surfaces and the mechanisms that ventilate and perfuse those surfaces
Term
Three problems with gas exchange in humans
Definition
skin is a barrier, surface area:volume relationships, and keeping membrane wet
Term
Gills
Definition
usually belong to water-breathing animals. they are highly branched and folded extensions of the body surface that provide a large surface area for gas exchange with water. can be external or internal. receive a constant supply of water through swimming, pumps, or operculum.
Term
Lungs
Definition
generally belong to air-breathing animals. they are internal cavities for respiratory gas exchange with air. they have a large surface area because they are highly divided and because they are elastic (they can be inflated with air and deflated). less efficient than gills, but water loss is controlled by passing air over increasingly wet membranes
Term
Tracheae
Definition
a network of air-filled tubes that branch through all tissues of the insect body and serve as the respiratory gas exchange system for insects. the insect respiratory system communicates with the outside environment through gated openings in the sides of the abdomen called "spiracles". the spiracles open to allow gas exchange and close to decrease water loss. they open into the tracheae tubes, which feed into trachioles, then air capillaries (the actual gas exchange surfaces).
Term
Metabolism
Definition
the rate of metabolism determines the rate of oxygen consumption. greater activity and greater size = greater need for oxygen
Term
Countercurrent blood flow
Definition
internal gills of fishes are supported by gill arches, which support the gill filaments, which are covered with rows of evenly spaced folds, or lamellae, the actual gas exchange surfaces. blood flows THROUGH the lamellae in the direction opposite to the flow of water OVER the lamellae. this countercurrent flow optimizes the PO2 gradient between water and blood, making gas exchange more efficient.
Term
Bird lungs/air sacs
Definition
use unidirectional ventilation to prevent dead space (air remaining in lungs after exhilation). in additon to lungs, birds have air sacs at several locations in their body. the air sacs receive inhaled air, but they are not gas exchange surfaces. they hold air so that air can continue to flow unidirectionally, because it all enters and leaves through one opening (the trachea).
Term
Alveoli
Definition
tiny, thin-walled air sacs that are the sites of gas exchange in mammals. for their small size, have a very large surface area (1/4 the size of a basketball court). surrounding the thin-walled alveoli are networks of thin-walled capilarries. gas exchange between the oxygen in the alveoli and CO2 in the blood occurs at these sites of little diffusion length.
Term
Hemoglobin
Definition
a protein consisting of four polypeptide subunits, each of which surrounds a heme group (the iron-containing ring structure that can reversibly bind a molecule of O2). has the ability to pick up or release O2.
Term
Bicarbonate Ions
Definition
the form in which CO2 (a waste product) is transported by the blood to the lungs for breathing out. HCO3
Term
Open Circulatory System
Definition
system in which the extracellular fluid is the same as the fluid in the circulatory system and is called "hemolymph". a muscular pump, or heart, helps move the hemolymph through vessels leading to different regions of the body. the fluid leaves the vessels to trickle through the tissues before returning to the heart (generally through small openings called ostia). found in arthropods, mollusks, and some other invertebrate groups.
Term
Closed Circulatory System
Definition
system that completely contains the circulating fluid (blood) in a continuous system of vessels. blood cells and large molecules stay within the system, but water and low-molecular-weight solutes leak out of the smallest vessels, the capillaries, which are highly permeable. found in vertebrates and a few invertebrate groups, like annelids.
Term
Advantages of closed circulatory systems over open circulatory systems
Definition
1. fluid can flow more rapidly and can therefore transport nutrients and wastes to and from tissues more rapidly.
2. by changing the diameter of specific vessels, closed systems can control the flow of blood to selective tissues and organs to match their needs.
3. specialized cells and large molecules that aid in transporting hormones and nutrients can be kept in the vessels but can drop their cargo in tissues where it is needed.
Term
Double Circuit Circulation (in closed circulatory systems)
Definition
in birds and mammals, blood is pumped from the heart to the lungs and back to the heart in a PULMONARY CIRCUIT, and then from the heart to the rest of the body and back to the heart in a SYSTEMIC CIRCUIT.
Term
Single Circuit Circulation
Definition
in fishes, blood is pumped from the heart to the gills and then to the tissues of the body and back to the heart
Term
Path of blood flow in humans
Definition
deoxygenated blood from vena cava (superior and inferior) flows into right atrium -> right ventricle -> lungs (to be oxygenated) -> left atrium -> left ventricle -> aorta out to rest of body.
Term
Cardiac Cycle
Definition
*both sides of the heart contract at the same time. contraction of the two atria, followed by contraction of the two ventricles, and then relaxation
Term
Systole
Definition
when the ventricles contract
Term
diastole
Definition
when the ventricles relax
Term
Sinoatrial Node
Definition
a group of modified cardiac muscles located at the junction of the superior vena cava and right atrium, this generates a series of rhythmic action potentials that spread through the atria, making them contract.
Term
Atrioventricular Node
Definition
a nodule of modified cardiac muscle cells located at the junction of the atria and ventricles. it is stimulated by the depolarization of the atria, and it generates action potentials that are conducted to the ventricles via the bundle of His. allows blood to pass through ventricles and on to arteries
Term
Components of human circulatory system
Definition
arteries and arterioles carry blood away from the heart, veins and veinules carry blood to the heart, capillaries are the sites of gas exchange
Term
Blood Composition
Definition
plasma, red blood cells (erythrocytes), white blood cells (leukocytes), and platelets- cell fragments of bone marrow that are essential for blood clotting
Term
Plasma
Definition
makes up 50-60% of the blood; made up of water, protein, dissolved nutrients, dions, hormones, and antibodies
Term
Oxygen Partial Pressure
Definition
the amount of oxygen present; it determines the activity of hemoglobin. when pp is high, oxygen is taken up. when pp is low, oxygen is given off.
Term
Lymphatic System
Definition
fluid which does not reenter capillary at venous (back to heart) end goes into lymphatic system. the purpose of the lymphatic system is to return interstitial fluid (fluid around the cells) to the blood. once the fluid enters the lymphatic system, it is called lymph. small lymphatic capillaries eventually progress into larger vessels and ultimately into two large lymphatic vessels called the "thoracic ducts", which empty into large veins at the base of the neck
Term
Lymph nodes
Definition
found along the major lymphatic vessels, they are a major site of lymphocyte production and of the phagocytic action that removes microorganisms and other foreign materials from the circulation
Term
Osmoconformers
Definition
most marine invertebrates, they equilibrate their extracellular osmolarity with the ocean water.
Term
Osmoregulators
Definition
other marine animals, they maintain extracellular fluid osmolarities much lower than seawater.
Term
Nitrogenous waste
Definition
produced by the metabolism of proteins and nucleic acids; obviously contain nitrogen. the most common form is ammonia (NH3). because of its high toxicity, ammonia is either excreted continuously to prevent its accumulation or it is detoxified by conversion into urea or uric acid.
Term
Ammonotelic
Definition
animals that excrete ammonia; aquatic invertebrates and bony fishes
Term
Uricotelic
Definition
animals that conserve water by excreting nitrogenous wastes mostly as uric acid; insects, reptiles, birds, and some amphibians. uric acid is not very soluble in water, and is excreted as a semisolid (bird poop). so the uricotelic animal loses very little water and gets rid of nitrogenous waste
Term
Ureotelic
Definition
animals that excrete urea as their primary nitrogenous waste product; mammals, amphibians, and carilaginous fishes (sharks and rays). urea is quite soluble in water, and it excretion usually results in a large loss of water. however, mammals have evolved excretory systems that conserve water by producing concentrated urea solutions.
Term
Contractile Vacuole
Definition
simplest excretory system; found in protozoans and primitive multicellular animals. food and water are forced in and it keeps growing until it releases the excess waste
Term
Protonephridia
Definition
the simplest tubule excretory system, a protonephridium is made up of a flame cell (with beating cilia) and a tubule. the beating of the cilia causes a slight negative pressure in the tubule, and extracellular fluid is filtered into the tubule cells. the filtrate flows toward excretory pores, and along the way specific ions and molecules are reabsorbed and secreted. the end result is conservation of ions and excretion of water and wastes.
Term
Metanephridia
Definition
in annelids (the earthworm for example), each segment contains a pair of metanephridia. each metanephridium begins as a ciliated, funnel-like opening called a "nephrostome". the nephrostome resides in one segment but continues into the next segment. the tubule ends in a pore, called the "nephridiopore", that opens to the outside of the animal. there is reabsorption and secretion along the way and what leaves the nephridiopores is a dilute urine containing nitrogenous wastes and other solutes
Term
Malphigian Tubules
Definition
blind-ended tubules that open into the gut between the midgut and hindgut. they use active transport of cells to transport uric acid, potassium ions, and sodium ions from the the extracellular fluid into the tubules. the ions are later reabsorbed, leaving uric acid and other wastes in the rectum, which the insect then secretes.
Term
Nephron
Definition
the functional excretory unit in vertebrates, many are grouped together into a kidney (mechanism primarily geared to get rid of nitrogenous waste). forms urine through three main processes: filtration, tubular reabsorption, tubular secretion.
Term
Kidney
Definition
3 parts: cortex, medulla, and pelvis. composed of millions of nephridia, blood enters via renal artery. fluid moves from blood into bowman's capsule. water and salts are removed and then proceed to proximal convoluted tubule, then down loop of Henle
Term
Hormones
Definition
chemical signals that are released by certain types of cells and that influence the activities of other cells at a distance; transported by the blood. endocrine cells secrete the chemical signals, target cells have receptors for those signals.
Term
Testosterone
Definition
at 7 weeks- indifferent gonad. if fetus is male- testosterone is secreted, which stimulates formation of male organs. if fetus is female- no testosterone is secreted, gonads develop into female organs.
Term
Endocrine glands
Definition
aggregations of endocrine cells form these secretory organs. the name reflects the fact that these glands secrete their products directly into the extracellular fluid, which they pass into the blood.
Term
Adrenal Glands
Definition
central part is the adrenal medulla, outer part is the adrenal cortex. adrenal medulla is responsible for the secretion of adrenaline and noradrenaline. adrenal cortex secretes hormones involved with physiological homeostasis.
Term
Pituitary Gland
Definition
sits in a depression at the bottom of the skull; generally categorized into two parts, the anterior pituitary and posterior pituitary.
Term
Posterior Putitary Hormones
Definition
include antidiuretic hormone (ADH)- increases amount of water conserved by the kidneys, and oxytocin- stimulates the uterine contractions that deliver the baby, also brings about flow of milk from the mother's breast
Term
Anterior Pituitary Hormones
Definition
four peptide and protein hormones that act as trophic hormones (meaning they control the activities of other endocrine glands)-thyrotropin, luteinizing hormone, follicle-stimulating hormone, and corticotropin. other peptide and protein hormones include growth hormone, prolactin, melanocyte-stimulating hormone, enkephalins, and endorphins.
Term
Endorphins
Definition
found as a result of a study on opiates. they are natural pain killers, found in runners
Term
Thyroid Gland
Definition
this gland wraps around the front of the trachea and expands into a lobe on either side. there are two cell types in the thyroid gland, each producing a different hormone. epethelial cells, which make up round structures called follicles, produce, store, and release thyroxin. cells in the spaces between follicles produce calcitonin.
Term
Parathyroid Glands
Definition
these are four tiny structures embedded in the posterior surface of the thyroid gland. their single hormone product, parathyroid hormone (PTH), is the most important hormone in the regulation of blood calcium levels.
Term
Insulin and Glucagon
Definition
hormones secreted from the pancreas, a large gland located just below the stomach, that regulate blood glucose concentrations. Insulin allows glucose to enter cells. Glucagon stimulates the liver to break down more stored glycogen and release glucose into the blood.
Term
Neuron
Definition
the cellular component of the nervous system. it can generate and transmit electical signals, known as nerve impulses, or action potentials. its anatomy consists of dendrites extending of a cell body (which contains the nucleus and organelles), the axon (conducts action potentials away from the cell body), and the axon terminal where the synapse (connection b/w two neurons) occurs.
there are 3 types: sensory, motor, and interneurons.
Term
Divisions of nervous system
Definition
Somatic: deals with processes under conscious control Autonomic: deals with processes not consciously controlled; two divisions: sympathetic and parasympathetic. sympathetic excites and parasympathetic relaxes
Term
Sodium-Potassium Pump
Definition
a major ion transporter in the plasma membranes of neurons. it actively expels Na+ ions from inside the cell, exchanging them for K+ ions outside the cell
Term
Acetylcholine (ACh)
Definition
the neurotrasmitter (chemical messenger molecules) used by all vertebrate neuromuscular synapses, it is released by exocytosis when the membrane of a vesicle fuses with the presynaptic membrane of the axon terminal
Term
Sensory Receptor Cells
Definition
sometimes called sensors or receptors, they convert physical and chemical stimulli into neural signals. these signals are then transmitted to the central nervous system for processing and interpretation.
Term
Chemoreceptors
Definition
receptor proteins that bind to various molecules (via their ligands) and are responsible for smell and taste
Term
Olfaction
Definition
the sense of smell; depends on chemoreceptors. in vertebrates, olfactory sensors are neurons embedded in a layer of epithelial tissue at the top of the nasal cavity. an "odorant" is a molecule that activates an olfactory receptor protein.
Term
Gustation
Definition
the sense of taste; depends on clusters of chemoreceptors called taste buds. the taste buds are also embedded in the epithelium
Term
mechanoreceptors
Definition
the sensory cells that respond to mechanical forces
Term
Ear Anatomy
Definition
the prominent structures on the sides of a human head are the pinnae. the pinnae collect sounds and direct them into the auditory canal, which leads to the actual hearing apparatus in the middle ear and the inner ear. the eardrum, or tympanic membrane, covers the end of the auditory canal and vibrates in response to pressure waves traveling down the auditory canal.
Term
Middle Ear
Definition
contains three delicate bones called "ossicles". they are individually named the malleus, incus, and stapes. these ossicles transmit the vibrations of the tympanic membrane to another flexible membrane called the oval window. behind the oval window is the fluid-filled inner ear, and movements of the oval window impart pressure changes to that enclosed fluid. these pressure waves are later trasduced into action potentials.
Term
Inner Ear
Definition
a bony structure consisting of two sets of canals: one is the organ of balance, the vestibular system; the other is the organ of hearing, the cochlea (which is long and coiled). a cross section of the cochlea reveals that it is composed of three parallel canals separated by two membranes: Reissner's membrane and the basilar membrane. sitting on the basilar is the organ of Corti, which transduces pressure waves into action potentials.
Term
The vestibular system in the inner ear
Definition
consists of three bony "semicircular canals" and two bony chambers called the "saccule" and the "utricule". the entire vestibular system is filled with a fluid called endolymph. projecting into the base of each canal is a gelatinous swelling called a cupula that encloses a cluster of hair cell stereocilia. when the shifting endolymph pushes on the cupula, it bends the stereocilia. the stereocilia in the saccule and utricule are embedded with otoliths, gelatinous structures containing crystals of calcium carbonate. when the head changes position in any way, gravitational forces are exerted on the otoliths and bend the stereocilia, releasing neurotransmitters.
Term
Rhodopsins detect light
Definition
*responsible for photosensitivity. a rhodopsin molecule consists of a protein, opsin (which alone is not photosensitive), and an associated nonprotein light-absorbing group, 11-cis-retinal, cradled in the center of the opsin and covalently bound to it. when 11-cis-retinal absorbs a photon of light energy, it changes into a different isomer of retinal, called all-trans-retinal. this change puts a strain on the bonds between retinal and opsin, changing the conformation of opsin. this change signals the detection of light.
Term
Rod cells
Definition
named for its shape, it is a modified neuron that does not produce action potentials. instead, rod cells release neurotransmitter from their bases where they form synapses with the next neurons in the visual pathway. each rod cell has an outer segment, inner segment, and a synaptic terminal. the outer segment captures photons of light passing through the rod cell. the inner segment contains the nucleus and junk. the synaptic terminal is where the rod cell communicates with other neurons.
Term
Cone cells
Definition
also named for their shape, these cells are responsible for the less sensitive color vision (rod cells pick up the highly sensitive black and white vision). they have a low sensitivity to light and allow us to see colors. proteins cause reactions to different absorptions of light- red, blue, green...
Term
Ocelli
Definition
found in many invertebrates (namely grasshoppers), they are light receptors that do not function as eyes. consists of eye cup and receptors
Term
Compound eyes
Definition
use many closely packed units called ommatidia, each of which is independent. relies on the formation of an image.
humans have camera-type eyes
Term
3 characteristics of sound
Definition
pitch, intensity, and tone quality
Term
Lateral line systems of fishes
Definition
composed of clusters of sensory cells. pressure waves deflect hair cells producing stimulus. used to sense water movement (speed of swimming), current locations and intensities, and prey movement.
Term
homolecithal/telolecithal distribution
Definition

homolecithal eggs have evenly distributed yolk in the center of the egg

telolecithal eggs have yolk concentrated at one poll in the egg

Term
euryhaline/stenohaline
Definition

euryhaline will have a broad acceptance of salts (like a tide pool)

stenohaline will have a narrow acceptance of salts

Term
founder effect/bottleneck effect
Definition

founder effect: the loss of genetic variation that occurs when a new population is established by a small population from a larger population

bottleneck effect: a "genetic bottleneck" that results when a considerable percentage of a population is killed or somehow made unable to reproduce offspring.

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