Chapter 11 BIOENERGETICS: The role of ATP

Question 1

is the study of the energy changes accompanying biochemical reactions

Answer 1

Bioenergetics or biochemical thermodynamics

Question 2

Biologic systems are essentially ____ and use chemical energy to power living processes

Answer 2

isothermic

Question 3

is that portion of the total energy change in a system that is available for doing work—that is, the useful energy, also known as the chemical potential

Answer 3

Gibbs change in free energy (ΔG)

Question 4

• states that the total energy of a system, including its surroundings, remains constant
  -It implies that within the total system, energy is neither lost
  nor gained during any change

Answer 4

first law of thermodynamics

Question 5

• states that the total entropy of a system must increase if a process is to occur spontaneously

Answer 5

second law of thermodynamics

Question 6

is the extent of disorder or randomness of the system and becomes maximum as equilibrium is approached

Answer 6

Entropy

Question 7

Under conditions of constant temperature and pressure, the relationship between the free-energy change (ΔG) of a reacting system and the change in entropy (ΔS) is expressed by the following equation

Answer 7

ΔG = ΔH−TΔS

Question 8

If ΔG is negative, the reaction proceeds spontaneously with loss of free energy

Answer 8

Exergonic

Question 9

if ΔG is positive, the reaction proceeds only if free energy can be gained

Answer 9

Endergonic

Question 10

The vital processes—for example, synthetic reactions, muscular contraction, nerve impulse conduction, and active transport—obtain energy by chemical linkage, or ____

Answer 10

coupling

Question 11

The exergonic reactions are termed ___

Answer 11

catabolism

Question 12

synthetic reactions that build up substances are termed ____

Answer 12

anabolism

Question 13

The combined catabolic and anabolic processes constitute ____

Answer 13

metabolism

Question 14

the principal high-energy intermediate or carrier compound is

Answer 14

adenosine triphosphate (ATP)

Question 15

___ utilize simple exergonic processes; eg, the energy of sunlight (green plants)

Answer 15

Autotrophic organisms

Question 16

___ organisms obtain free energy by coupling their metabolism to the breakdown of complex organic molecules in their environment

Answer 16

heterotrophic

Question 17

• plays a central role in the transference of free energy
  from the exergonic to the endergonic processes
• nucleotide consisting of the nucleoside adenosine
  (adenine linked to ribose), and three phosphate groups

Answer 17

adenosine triphosphate (ATP)

Question 18

connects those processes that generate

~(P) to those processes that utilize ~ (P)

Answer 18

ATP/ADP cycle

Question 19

True or False

ATP is able to act as a donor of high-energy phosphate to form those compounds below it. Likewise, with the necessary enzymes, ADP can accept high-energy phosphate to form ATP from those compounds above ATP in the table.

Answer 19

True

Question 20

There are three major sources of ~(P) taking part in energy

conservation or energy capture

Answer 20

1. Oxidative Phosphorylation
2. Glycolysis
3. The citric acid cycle

Question 21

is the greatest quantitative source of ~(P) in aerobic organisms. ATP is generated in the mitochondrial matrix as O2 is reduced to H2O by electrons passing down the respiratory chain

Answer 21

Oxidative Phosphorylation

Question 22

A net formation of two ~(P) results from the formation of lactate from one molecule of glucose, generated in two reactions catalyzed by phosphoglycerate
kinase and pyruvate kinase, respectively

Answer 22

Glycolysis

Question 23

One ~(P) is generated directly in the cycle at the succinate thiokinase step

Answer 23

The citric acid cycle

Question 24

act as storage forms of high-energy phosphate and include creatine phosphate, which occurs in vertebrate skeletal muscle, heart, spermatozoa, and brain, and arginine phosphate, which occurs in invertebrate muscle

Answer 24

Phosphagens

Question 25

important for the maintenance of energy homeostasis in cells

Answer 25

Adenylate kinase

Question 26

UTP, GTP, and CTP can be synthesized from their diphosphates

Answer 26

nucleoside diphosphate (NDP) kinases

Question 27

catalyze the formation of nucleoside diphosphates

from the corresponding monophosphates

Answer 27

nucleoside monophosphate (NMP)