22 terms

4.B Competition & Cooperation and 4.C Environmental Interactions

AP Biology
metabolic pathway
Begins with a specific molecule, which is then altered in a series of defined steps, resulting in a certain product.
catabolic pathways
Metabolic pathways that release energy by breaking down complex molecules into simpler compounds.
anabolic pathways
Metabolic pathways that consume energy to build complicated molecules from simpler ones.
The study of how organisms manage their energy resources.
free energy
Measures the portion of a system's energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell.
endergonic reaction
Reaction that absorbs free energy from its surroundings.
exergonic reaction
Reaction that proceeds with a net release of free energy.
energy coupling
The use of an exergonic process to drive an endergonic one.
A chemical agent that speeds up a reaction without being consumed by the reaction.
A catalytic protein.
activation energy
The amount of energy needed to push the reactants over an energy barrier.
enzyme-substrate complex
When an enzyme binds to its substrate, it forms:
active site
A pocket or groove on the surface of the enzyme.
Non-protein helpers that may be bound tightly to the enzyme as a permanent resident, or may bind loosely and reversibly along with the substrate.
If the cofactor is an organic molecule.
competitive inhibitors
Reduce the productivity of enzymes by blocking substrates from entering active sites.
noncompetitive inhibitors
Impede enzymatic reactions by binding to another part of the enzyme (other than the active site).
allosteric regulation
When a protein's function at one site is affected by the binding of a regulatory molecule to a separate site.
feedback inhibition
A metabolic pathway is switched off by the inhibitory binding of its end product to an enzyme that acts early in the pathway.
keystone species
A plant or animal that plays a unique and crucial role in the way an ecosystem functions.
gene duplication
The generation of extra copies of a gene in a genome over evolutionary time. A mechanism by which genomes can acquire new functions.
temperature-dependent sex determination (TDSD)
In some reptiles, when the temperature during a critical period of embryonic development determines the gender of the offspring.