Chapter 8

Question 1

the form of cellular respiration found in some prokaryotes in which a molecule other than oxygen is used in the ATP-producing process

Answer 1

anaerobic respiration

Question 2

the partial or full loss of electrons from a substance

Answer 2

oxidation

Question 3

substance-the electron donor-from which the electrons are lost during oxidation

Answer 3

oxidized

Question 4

the partial or full gain of electrons to a substance

Answer 4

reduction

Question 5

substance-the electron acceptor-that gains electrons during reduction

Answer 5

reduced

Question 6

coupled oxidation-reduction reaction in which electrons are removed from a donor molecule and simultaneously added to an acceptor molecule

Answer 6

redox reactions

Question 7

a coenzyme that serves as an electron carrier

Answer 7

nicotinamide adenine dinucleotide (NAD+)

Question 8

stage of cellular respiration in which sugars such as glucose are partially oxidized and broken down into smaller molecules

Answer 8

glycolysis

Question 9

an enzymecatalyzed reaction that transfers a phosphate group from a substrate to ADP

Answer 9

substrate-level phosphorylation

Question 10

stage of cellular respiration in which the threecarbon molecules pyruvate is converted into a 2-carbon acetyl group that is completely oxidized to carbon dioxide

Answer 10

pyruvate oxidation

Question 11

series of reactions in which acetyl groups are oxidized completely to carbon dioxide and some ATP molecules are synthesized

Answer 11

citric acid cycle

Question 12

synthesis of ATP in which ATP synthase uses an H+ gradient built by the electron transfer system as the energy source to make the ATP

Answer 12

oxidative phosphorylation

Question 13

stage of cellular respiration in which high-energy electrons produced from glycolysis, pyruvate oxidation, and the citric acid cycle are delivered to oxygen by a sequence of electron carriers

Answer 13

electron transfer system

Question 14

a membrane-spanning protein complex that couples the energetically favorable transport of protons across a membrane to the synthesis of ATP

Answer 14

ATP synthase

Question 15

series of reactions in which acetyl groups are oxidized completely to carbon dioxide and some ATP molecules are synthesized

Answer 15

citric acid cycle/ Krebs cycle/ tricarboxylic acid cycle

Question 16

stage of cellular respiration in which the 3carbon molecule pyruvate is converted into a 2-carbon acetyl group that is completely oxidized to carbon dioxide

Answer 16

pyruvic acid oxidation

Question 17

series of electron carriers that alternately pick up and release electrons ultimately transferring them to their final acceptor, oxygen

Answer 17

mitochondrial electron transfer system

Question 18

protein with a heme prosthetic group that contains an iron atom

Answer 18

cytochromes

Question 19

stored energy that contributes to ATP synthesis as well as to the cotransport of substances to and form mitochondria

Answer 19

proton-motive force

Question 20

model proposing that mitochondrial electron transfer produces an H+ gradient and that the gradient powers ATP synthesis by ATP synthase

Answer 20

chemiosmotic hypothesis

Question 21

process in which electrons carried by NADH are transferred to an organic acceptor molecule rather than to the electron transfer system

Answer 21

fermentation

Question 22

reaction in which pyruvate is converted into lactate

Answer 22

lactate fermentation

Question 23

reaction in which pyruvate is converted into ethyl alcohol and CO2 in a 2-step series that also converts NADH into NAD+

Answer 23

alcoholic fermentation

Question 24

organism in which fermentation is he only source of ATP

Answer 24

strict anaerobes

Question 25

an organism that can live in the presence or absence of oxygen using oxygen when it is present and living by fermentation under anaerobic conditions

Answer 25

facultative anaerobes

Question 26

cell with an absolute requirement for oxygen to survive unable to live solely by fermentations

Answer 26

strict aerobes

Question 27

the form of cellular respiration found in eukaryotes and many prokaryotes in which oxygen is a reactant in the ATP-producing process

Answer 27

aerobic respiration