Action Potential : a change in the permeability of the neuron membrane allowing for a change in electric potential

ATP Synthase (ATP Synthesizing Enzyme) : a protein structure embedded in the membrane of the thylakoid of a chloroplast, the inner membrane of a mitochondrion, and the plasma membrane of bacteria; protons pass through this channel and ADP and P are combined to make ATP

B-cells : lymphocytes that develop and mature in the bone marrow that produce plasma cells which make antibodies (humoral immunity)

Biotic Potential : the maximum rate that a population can increase under optimal conditions

Chemosynthesis : process by which inorganic molecules are used to form energy-rich bonds in carbohydrates

Cohesion-Tension Model : describes the movement of water against gravity in the xylem based on 3 factors

1. continuous flow of water from the environment into the root
2. water molecules stick to each other and to the sides of their container as a result of hydrogen bonding (cohesion)
3. transpiration causes a slight vacuum at the stomates (tension)

Cytokinesis : the division of the cytoplasm following mitosis or meiosis

Cytotoxic T-cells : lymphocytes that develop and mature in the bone marrow and seek out and kill infected cells and cancer cells

DNA Polymerase : enzyme used to catalyze the assembly of a complementary nucleotide sequence during replication

DNA Replication : the process by which a strand of DNA produces an identical copy of itself

Ecosystem : biological area defined by its biotic and abiotic factors through which energy flows and nutrients cycle

Electron Transport System : a series of cytochromes and proteins which transport electrons and release their energy; energy can be used to synthesize ATP

Entropy : a measure of disorganization

Environmental Resistance : the environmental factors which limit the biotic potential of a population

Exons : those pieces of a eukaryotic gene that need to be transcribed and translated

Homeostasis : sustaining a relatively stable internal environment

Interneuron (Association Neuron) : a neuron, located in the central nervous system, that relays information between sensory neurons and motor neurons

Interphase : the longest phase of the mitotic cell cycle during which the cell grows and carries out regular metabolic functions; includes replication of DNA

Introns : those intervening pieces of a eukaryotic gene that need to be edited out following transcription

Motor Neuron : a neuron that sends an impulse to an effector - either a gland or a muscle

Neuron : a nerve cell that transmits electrical and/or chemical impulses

Oxidation Reaction : reaction characterized by a loss of electrons

Plasmid : circular piece of bacterial DNA that is not part of the genomic DNA

Pressure-Flow Hypothesis : model used to explain the transport of products of photosynthesis in the phloem cells of plants

Reduction Reaction : reaction characterized by a gain of electrons

Restriction Enzyme : an enzyme that cuts DNA at a restriction site characterized by a specific sequence of nucleotides

Sensory Neuron : a neuron that gets information from the external or internal environment and carries it to an interneuron in the central nervous system

Sliding-Filament Hypothesis : describes the movement of the actin filaments over the myosin filaments within a myofibril

Speciation : the formation of a new species

Spliceosome : enzyme(s) that perform(s) post transcriptional modification - remove(s) introns

Successful : the extent to which an organism's genes are perpetuated in the following generation

Transcription : the construction of an mRNA strand that is complementary to a DNA strand

Transduction : transfer of DNA from cell to cell via a virus

Transformation : the general movement of DNA from one organism or cell to another organism or cell

Translation : the sequencing of amino acids according to the mRNA sequence; performed by a ribosome in the cytoplasm of a cell

Transpiration : evaporation of water from a leaf

Trophic Level : a position in the food chain; feeding level of an organism