Molecule

group of chemically bonded atoms that possesses characteristics independent of the atoms themselves

Muscle tissue

dedicated to producing movement; three types include skeletal, cardiac, and smooth

muscular system

consists of skeletal muscles, tendons that connect muscles to bones and ligaments that attach bones together to form joints

mutagen

substance that induces mutations

mutation

permanent change in DNA sequence

natural selection

process in which individuals of a species carrying certain mutations are better able to survive and reproduce in their natural environment than others members of the species (survival of the fittest)

nervous system

serves as the body's control system; consists of the brain, spinal cord and nerves

nervous tissue

structure for the brain, spinal cord, and nerves made up of neurons that send electrical impulses throughout the body

Neurons

specialized cells that make up the nervous system and transmit electrial impulses

neutron

neutral subatomic particle found in the nucleus of an atom

nitrogenous base

molecule found in DNA and RNA that encodes the genetic information in cells

nucleic acid

chain of nucleotides

nucleoid

condensed DNA of a cell

nucleolus

small body within the nucleus that functions to produce ribosomes that are then moved to the cytoplasm to make cell proteins

nucleotide

molecule that consists of a pentose, a phosphate group, and a nitrogenous base

Nucleus

central region of an atom; large organelle that is the control center of the entire cell

orbital shell

arrangement of electrons within a specific region around the nucleus

organ

two or more tissue types that work together to perform a specific function

organ system

group of organs in an organism working together to perform a specific function

organelle

tiny organ

organic chemistry

study of the structure and properties of carbon compounds

organism

living body made up of several organ systems

oxidation

electron donation by a chemical group that leaves that group with one less electron and a more positive charge

light-year

distance that light will travel within a year

kinetic energy

the energy of motion

leuokocytes

white blood cells

Kelvin

metric temperature scale defined by an absolute zero reference point (0 Kelvin = -273 degree Celcius, the temperature at which molecular motion ceases)

Joule

a common metric unit of energy ( 1 calorie= 4.2 Joules)

isotope

atoms with the same number of protons but differing numbers of neutrons

ionic

electrical attraction between ions of opposite charges

ion

positively or negatively charged atom

Expiration

act of exhaling carbon dioxide from the body

exicision repair

mechanism that inspects the DNA for damage and attempts to repair it

Eukarya

organism that contains cellular organelles; organism that has cells that contain nuclei (protists, plants, fungi, and animals)

Etymology

history of a given word, a word's origin

latent heat

heat per mass needed for a phase change at a constant temperature

lateral

toward the outer sides of the body or body structure (opposite of medial)

Law of Conservation of Energy

if a system is closed, the total amount of energy in the system does not change; however, energy can be changed from one form to another

leukocytes

white blood cells

Lewis structure

symbolic representation of covalent bonding between atoms

lungs

paired organs that take in oxygen and exhale carbon dioxide

lymphatic system

supports the immune system by housing and transporting white blood cells to and from lymph nodes; returns fluid that has leaked from the cardiovascular system back into the blood vessels; consists of the lymph nodes, the lymph vessels that carry lymph, the spleen, the thymus, and the tonsils

lyse

latin word for break; used in biology and chemistry to mean rupture or destruction of the cell membrane, a cell structure, or a molecule

lysosome

organelle containing digestive enzymes capable of disposing of cellular debris and worn cellular parts

mass

quantity of matter within an object

mass number

total number of protons and neutrons found within the nucleus of an atom matter anything that takes up space and has mass

medial

toward the middle of the body or body structure (opposite of lateral)

meiosis

process by which gametes reduce their DNA content

metabolic pathways

chemical reactions within a cell

metabolism

chemical reactions in living organisms used to maintain life

metalloids

elements that may accept or donate electrons readily; possess a mixture of metallic and nonmetallic properties

metals

elements that readily donate electrons and are good conductors of electricity; donate highly conductive electrons to their environment

metaphase plate

disc extending across the nuclear area on which the chromosomes are found at metaphase just prior to separation of the chromosomes during mitosis

microtubules

cellular tracks that form the mitotic spindle during mitosis

microvilli

microscopic projections of tissues that make up the villi

midsagittal section

sagittal section made down the median of the body

mismatch repair

mechanism that scans over the DNA to find any mismatches of nitrogenous bases

mitochondrion

powerhouse of the cell

mitosis

process of cell duplication in which two daughter cells recieve exactly the same nuclear material as the original cell

parasympathetic nerve

branch of the autonomic nervous system that is active when a person is eatign or at rest

pathogen

any disease-causing agent

pentose

type of sugar

perforin

pore-forming protein

peripheral nervous system

branch of the nervous system that extends outside of the central nervous system and consists of the cranial and spinal nerves

peristalsis

rhythmic contractions of the stomach and intestines that propel food toward the colon and anus

peroxisome

organelle used to rid the body of toxic components

pH

measure of hydrogen ion concentration within a solution; the scale used to measure the strength of acidic solutions; pH= -log (hydrogen ion concentration)

pH indicator

chemical detector of hydrogen ions to visually determine acidity (color changes)

phagocytosis

engulfing of pathogens by white blood cells

phase transition

alteration of the physical state of a substance between a solid, liquid, and gas

phenotype

physical expression of genetic traits

phosphate group

molecule in the backbone of DNA and RNA that links adjoining bases together

photosynthesis

process carried out by green plants, green algae, and certain bacteria, in which the energy from sunlight is trapped by chlorophyll and used for synthesis of glucose

physical bonding

physical connection between atoms (or molecules) that does not alter the chemical nature of the atom (or molecules)

physiology

study of the function of the various organs and body systems

plasmids

small circular portions of DNA not associated with the nucleoid

polar molecule

possesses both positive and negative regions

posterior

toward the back of the body or body structure (opposite of anterior)

potential energy

stored energy

products

substances formed as the result of chemical reactions

prokaryote

single-celled organism lacking defined cellular organelles or a nucleus

protein

compound composed of a large number of amino acids joined in a particular type of chemical bond called a peptide bond

proximal

close to the origin of the body part or point of attachment (opposite of distal)

Punnett square

graphical way to show all possible combinations of alleles given the two parents genotypes

purine

nitrogenous base with two ring (adenine, guanine)

pyloric sphincter

muscle that separates the stomach from the duodenum and slowly releases chyme from the stomach into the small intestine (duodenum)

pyrimidine

nitrogenous base with one ring (thymine,cytosine, and uracil)

rate of change

speed at which something changes

ratio

relationship between two quantities

reactants

substances consumed or altered in a chemical reaction

reduction

electron acceptance by a chemical that produces a more negative charge on the group

reflex

automatic response to a stimulus that occurs when neurons transmit a message to the spinal cord, which in turn sends a message back to the muscles to react before the message is transmitted to the brain

reproductive system

main purpose is to produce offspring; houses hormones that encourage or suppress activities within the body (eg., libido and aggression) and influences the development of masculine or feminine body characteristics, consists of the testes and penis or the ovaries, vagina, and breasts

respiratory system

organ system that provides for air exchange by supplying tissues with oxygenated blood and removing carbon dioxide

ribosome

organelle responsible for synthesizing protein within the cell from amino acids

RNA (ribonucleic acid)

single-stranded molecule made from sugars, phosphates, and nitrogenous bases; required for the transfer and translation of the DNA code within a cell

sagittal section

cut made along a longitudinal plane that divides the body into right and left parts

salt

neutral product of an anion and a cation

saturated hydrocarbon

chemical structure composed entirely of single bonds

secretion

process of moving proteins outside of the cell

sensory neurons

neurons that carry messages from sense organs to the brain and spinal cord

sensory-somatic nervous system

part of the peripheral nervous system that consists of 12 pairs of cranial nerves, 31 pairs of spinal nerves, and associated ganglia; controls voluntary actions of the body

skeletal system

supports and protects the body and its organs; supplies a framework that, when used in conjunction with the muscles, creates movement; serves as storage for minerals, such as calcium and phosphorus, consists of bones, cartilage, ligaments, and joints

specific heat

energy required to raise one unit of mass in a substance by 1 degree of celcius

stem cells

can divide and remain undifferentiated; gives rise to a variety of more-specialized cells

stimulus

change in the environment that triggers a physical response

substrate

molecule acted upon by an enzyme

superficial

toward or at the body surface (opposite of deep)

superior

toward the upper end of the body or body structure (opposite of inferior)

sympathetic nerve

branch of the autonomic nervous system that is activated when a person is excited or scared

synapse

fluid-filled gap that connects the axon of one nerve cell with the cell body of another

T cell

lymphocyte that is responsible for cellular immunity

zygote

mass of cells formed after an egg is fertilized and begins dividing

work

result of any change in energy

villi

finger-like projections in the mucosa of the small intestine lining; produce a pleated appearance; each villus is supplied with blood and has lymphatic vessels for absorption

vesicles

small membrane-bound sacs within the cytoplasm used to transport proteins or other substances in and out of a cell

ventral body cavity

contains all the structures within the chest and abdomen; the diaphragm divides the ventral cavity into the thoracic cavity (superior to the diaphragm); below the diaphragm are the abdominal and pelvic cavities

veins

blood vessels that transport unoxygenated blood from the capillaries back to the heart

valence electrons

electrons in the outermost shell of an atom

vacuole

basic storage unit of a cell that can hold various compounds

vaccine

inactivated form of a pathogen that stimulates the body to produce antibodies for future protection

urinary system

helps maintain the water and electrolyte balance within the body; regulates the acid-base balance of the blood; removes all nitrogen-containing wastes from the body

unsaturated hydrocarbons

a chemical molecule containing at least one double or triple bond

triple-point

temperature and pressure at which a substances will coexist as a solid, liquid, and gas

transverse section

cut made along a horizontal plane that divides the body into upper and lower regions; cross section

translation

process of protein reduction from messenger RNA

transcription

process of cells copying the instruction from the DNA into the RNA

trachea

airway that connects the larynx to the bronchial tubes; also known as the windpipe

tissue

collection of cells in an organism that have a similar function and structure

taxonomy

classification of organisms into universally accepted taxons; names reflect the organism's evolutionary hertiage

Epithelial Tissue

provides covering (such as skin tissue) or produces secretions (such as glandular tissue); commonly exists in sheets and does not have its own blood supply

Enzyme

protein catalyst; chemical that changes the rate of a chemical reaction in living tissue without itself being chemically altered; a chemical that breaks down proteins, carbohydrates and fats into nutrients that can be absorbed through the wall of the intestine into the bloodstream

Endoplasmic Reticulum (ER)

tubular transport network with the cell that appears as a stack of flattened membranous sacs

heat of vaporization

amount of heat necessary to cause a phase transition between a liquid and a gas

heterotroph

organism that cannot produce its own food

heterozygous

having recieved different alleles for a particular trait from each parent

homeostasis

a stable state in which all the needs of a body are met and all of the organ systems are working properly together

incomplete dominance

dominant and recessive genotypes interact to produce an intermediate phenotype

independent variable

does not depend on another variable; affects the dependant variable

inferior

toward the lower end of the body or body structure (opposite of superior)

homozygous

having recieved the same allele for a particular trait from both parents

immune system

tissues, cells and organs that work together to fight off illness and disease

immigration

act of individual moving into the region or country to live

hydrocarbon

compound whose structure is entirely composed of hydrogen and carbon atoms

homologous

similar in size and function

inspiration

act of breathing in oxygenated air

intermediate

between the medial and lateral aspects of the body or body structure

interferon

protein that inhibits the reproduction of a virus

integumentary system

protects internal tissues from injury, waterproofs the body, and helps regulate body temperatures; serves as a barrier to pathogens; consists of the skin, mucous membranes, hair, and nails

interphase

process that occurs prior to mitosis; occurs when the cell must duplicate its DNA, increase the amount of organelles and cytoplasm, and synthesize protein in preparation for cell division, 3 stages of interphase are Gap 1 (G1), Synthesis (S) and Gap (2)