Chapter 8 word list Flashcards
- the totality of an organism’s chemical reactions
- is an emergent property of life that arises from interactions between molecules within the cell
Metabolism
release energy by breaking down complex molecules into simpler compounds
catabolic pathways
consume energy to build complex molecules from simpler ones
Anabolic pathways
the capacity to cause change
energy
potential energy available for release in a chemical reaction
chemical potential energy
energy of the universe is constant
-energy can be transferred and transformed
-energy cannot be created or destroyed
also called the principle of conservation of energy
First Law of Thermodynamics
- During every energy transfer or transformation, some energy is unusable, often lost as heat
- every single transfer or transformation increases the entropy (disorder) of the universe
Second Law of thermodynamics
energy that can do work when temperature and pressure are uniform, as in a living cell
Free energy
- free energy decreases and the stability of a system increases
- only processes with a negative g are ____
- the system must either give up enthalpy (h must decrease), give up order (Ts must increase) or both
spontaneous
proceeds with a net release of free energy and is spontaneous
exergonic reaction
absorbs free energy from its surroundings and is non spontaneous
Endergonic reaction
renewable resource that is regenerated by addition of a phosphate group to ADP
ATP
a chemical agent that speeds up a reaction without being consumed by the reaction
Catalyst
a catalytic protein
enzyme
the initial energy needed to start a chemical reaction is called
activation energy
the reactant that an enzyme acts on is called its
substrate
the enzyme binds to its substrate, forming an
enzyme substrate complex
the region on the enzyme where the substrate binds
active site
______ of a substrate brings chemical groups of the active site into positions that enhance the ability to catalyze the reaction
Induced fit
non protein enzyme helpers
look at examples on notes
cofactors
organic cofactors
coenzymes
bind to the active site of an enzyme, competing with the substrate
Competitive inhibitor
bind to another part of an enzyme, causing the enzyme to change shape and making the active site less effective
Noncompetive inhibitor
- the term used to describe cases where a protein’s function at one site is affected by binding of a regulatory molecule at another site
- may either inhibit or stimulate an enzymes activity
allosteric regulation
