Chapter 8 VOCAB***

Question 1

catabolic pathways

Answer 1

metabolic pathways release energy by breaking down complex molecules to simpler compounds…breakdown pathways

Question 2

anabolic pathways

Answer 2

consume energy to build complicated molecules from simpler ones; they are sometimes called biosynthetic pathways

Question 3

bioenergetics

Answer 3

the study of how energy flows through living organisms

Question 4

energy

Answer 4

the capacity to cause change

Question 5

kinetic energy

Answer 5

energy associated with the relative motion of objects

Question 6

heat/ thermal energy

Answer 6

kinetic energy associated with the random movement of atoms or molecules

Question 7

Potential energy

Answer 7

energy that matter possesses because of its location or structure

Question 8

chemical energy

Answer 8

the potential energy available for release in a chemical reaction

Question 9

thermodynamics

Answer 9

study of energy transformations that occur in a collection of matter

Question 10

First law of thermodynamics

Answer 10

energy of the universe is constant; energy can be transferred and transformed, but it cannot be created or destroyed….also known as principle of conservation of energy

Question 11

entropy

Answer 11

a measure of disorder, or randomness…the more randomly arranged a collection of matter is, the greater the entropy

Question 12

second law of thermodynamics

Answer 12

every energy transfer or transformation increases the entropy of the universe…although order can increase locally, there is an unstoppable trend toward randomization of the universe as a whole

Question 13

spontaneous process

Answer 13

a process that can occur without an input or energy

Question 14

free energy

Answer 14

the energy that may be extracted from a system at constant temperature and pressure

Question 15

exergonic reaction

Answer 15

a net release of free energy

Question 16

spontaneous

Answer 16

it is energetically favorable not that it will occur rapidly

Question 17

endergonic reaction

Answer 17

one that absorbs free energy from its surroundings

Question 18

energy coupling

Answer 18

the use of an exergonic process to drive an endergonic one

Question 19

enzyme

Answer 19

a macromolecule that acts as a catalyst

Question 20

catalyst

Answer 20

chemical agent that speeds up a reaction without being consumed by the reaction

Question 21

activation energy

Answer 21

initial investment of energy for starting a reaction-the energy required to contort the reactant molecules so the bonds can break- is known as the free energy of activation or activation energy

Question 22

substrate

Answer 22

the reactant an enzyme acts on

Question 23

enzyme substrate complex

Answer 23

this is formed when the enzyme binds to its substrate

Question 24

active site

Answer 24

typically a pocket or groove on the surface of the enzyme where catalysis occurs

Question 25

induced fit

Answer 25

brings chemical groups of the active site into positions that enhance their ability to catalyze the chemical reaction

Question 26

cofactors

Answer 26

the non protein helpers for catalystic activity

Question 27

coenzyme

Answer 27

if the cofactor is an organic molecule, it is more specifically called a coenzyme

Question 28

competitive inhibitors

Answer 28

reduce the productivity of enzymes by blocking substrates from entering active sites

Question 29

noncompetitive inhibitors

Answer 29

do not directly compete with the substrate to bind to the enzyme at the active site…instead they impede enzymatic reactions by binding to another part of the enzyme

Question 30

allosteric regulation

Answer 30

the term used to describe any case in which a protein’s function at one site is affected by the binding of a regulatory molecule to a separate site

Question 31

cooperativity

Answer 31

this mechanism amplifies the response of enzymes to substrates..one substrate molecule primes an enzyme to act on additional substrate molecules more readily

Question 32

feedback inhibition

Answer 32

metabolic pathway is switched off by the inhibitory binding of its end product to an enzyme that acts early in the pathway

Question 33

metabolism

Answer 33

the totality of an organism’s chemical reactions

Question 34

metabolic pathway

Answer 34

begins with a specific molecule, which is then altered in a series of defined steps, resulting in a certain product