Chapter 4

Question 1

Kinetic energy

Answer 1

The energy of motion

Question 2

Potential energy

Answer 2

stored energy

Question 3

Thermodynamics

Answer 3

The study of the energy flow during chemical and physical reactions.

Question 4

Entropy

Answer 4

Disorder in thermodynamics

Question 5

Spontaneous reaction

Answer 5

Chemical or physical reaction that occurs without outside help

Question 6

Enthalpy

Answer 6

Potential energy in a system

Question 7

Endothermic

Answer 7

Reactions which absorb energy

Question 8

Exothermic

Answer 8

Processes which release energy

Question 9

Reactants

Answer 9

The atoms or molecules entering the reaction

Question 10

Free energy (ΔG)

Answer 10

The energy in a system which is available to do work

Question 11

Concentration gradient

Answer 11

The concentration difference that dives diffusion

Question 12

Equilibrium

Answer 12

A state of balance between opposing factors that push a reaction in either direction

Question 13

Exergonic reaction

Answer 13

Reaction that has a negative ‘Free Energy’ because it releases free energy

Question 14

Endergonic reaction

Answer 14

Reaction that can be produced only if free energy is supplied

Question 15

Catabolic pathway

Answer 15

Types of metabolic pathway in which energy is released by the breakdown of complex molecules to simpler compounds

Question 16

Anabolic pathway

Answer 16

Type of metabolic pathway in which energy is consumed to build complicated molecules from simpler ones; often called a biosynthetic pathway

Question 17

Energy coupling

Answer 17

The process by which ATP is brought in close contact with a reactant molecule involved in an endergonic reaction, and when the ATP is hydrolyzed, the terminal phosphate group is transferred to the reactant molecule.

Question 18

Coupled reaction

Answer 18

A reaction which occurs when an exergonic reaction is joined to an endergonic reaction, producing an overall reaction which is exergonic.

Question 19

ATP cycle

Answer 19

Continued breakdown and resynthesis of ATP

Question 20

Activation energy

Answer 20

The initial input of energy required to start a reaction

Question 21

Transition state

Answer 21

An intermediate arrangement of atoms and bonds that both the reactants and the products of a reaction can assume

Question 22

Catalyst

Answer 22

Substances with the ability to accelerate a spontaneous reaction without being changed by the reaction

Question 23

Enzyme

Answer 23

Proteins that accelerates the rate of a cellular reaction

Question 24

Conformation

Answer 24

The overall three-dimensional shape of a protein

Question 25

Enzyme-substrate complex

Answer 25

A non-covalent complex composed of a substrate bound to the active site of the enzyme.

Question 26

Cofactor

Answer 26

An inorganic or organic nonprotein group that is necessary for catalysis to take place

Question 27

Coenzyme

Answer 27

Organic cofactors that include complex chemical groups of various kinds

Question 28

Saturation

Answer 28

the state or process that occurs when no more of something can be absorbed, combined with, or added.

Question 29

Competitive enzyme inhibitors

Answer 29

An enzyme which resembles the normal substrate closely enough that it fits into the active site of the enzyme.

Question 30

Noncompetitive enzyme inhibitors

Answer 30

An inhibitor molecule that binds to the enzyme at a site other than the active site and, therefore, does not compete directly with the substrate for binding to the active site.

Question 31

Allosteric regulation

Answer 31

Specialized control mechanism for enzymes with an allosteric site, a regulatory outside the active site that may either slow or accelerate activity depending on the enzyme.

Question 32

Allosteric site

Answer 32

A regulatory site outside the active site

Question 33

Allosteric activator

Answer 33

Molecule that converts an enzyme with an allosteric site, a regulatory site outside the active site, from the inactive form to the active form.

Question 34

Allosteric inhibitor

Answer 34

Molecule that converts an enzyme with an allosteric site, a regulatory site outside the active site, from to the inactive form to the inactive form.

Question 35

Futile cycle

Answer 35

also known as a substrate cycle, occurs when two metabolic pathways run simultaneously in opposite directions and have no overall effect other than to dissipate energy in the form of heat.

Question 36

Feedback inhibition

Answer 36

In enzyme reactions, regulation in which the product of a reaction acts as a regulator of the reaction. Also referred to as end-product inhibition

Question 37

Enzyme activity

Answer 37

is affected by physical conditions, and the activity of some enzymes is subject to regulation. Measure enzyme activity at different pH values and see where it is most active.

Question 38

pH optimum

Answer 38

an enzyme will have an optimum pH for activity

Question 39

Temperature optimum

Answer 39

an enzyme will have an optimum pH for activity