Midterm II -- Ch. 9 -- Cellular Respiration

Question 1

fermentation

Answer 1

catabolic process; a partial degradation of sugars or other organic fuel that occurs w/o the use of oxygen.

Question 2

aerobic respiration

Answer 2

catabolic pathway in which oxygen is consumed as a reactant along w/ the organic fuel.

Question 3

cellular respiration

Answer 3

the catabolic pathways of aerobic and anaerobic respiration, which breaks down organic molecules and use an electron transport chain for the production of ATP.

Question 4

redox reaction

Answer 4

oxidation-reduction reactions; the transfer of one or more electrons from one reactant to another.

Question 5

oxidation

Answer 5

the loss of electrons from one substance.

Question 6

reduction

Answer 6

the addition of electrons to another substance.

Question 7

NAD+

Answer 7

(nicotinamide adenine dinucleotide); a coenzyme that cycles easily between oxidized (NAD+) and reduced (NADH) states, thus acting as an electron carrier.

Question 8

electron transport chain

Answer 8

a sequence of electron carrier molecules (membrane proteins) that shuttle electrons down a series of redox reactions that release energy used to make ATP.

Question 9

glycolysis

Answer 9

a series of reactions that ultimately splits glucose into pyruvate. Glycolysis occurs in almost all living cells, serving as the starting point for fermentation or cellular respiration.

Question 10

citric acid cycle

Answer 10

a chemical cycle involving 8 steps that completes the metabolic breakdown of glucose molecules begun in glycolysis by oxidizing acetyl CoA (derived from pyruvate) to carbon dioxide; occurs w/in the mitochondrion in eukaryotic cells and tin the cytosol of prokaryotes; together w/ pyruvate oxidation, the second major stage in cellular respiration.

Question 11

oxidative phosphorylation

Answer 11

the production of ATP using energy derived from the redox reactions of an electron transport chain; the third major stage of cellular respiration.

Question 12

substrate-level phosphorylation

Answer 12

the enzyme-catalyzed formation of ATP by direct transfer of a phosphate group to ADP from an intermediate substrate in catabolism.

Question 13

acetyl CoA

Answer 13

acetyl coenzyme A; the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme.

Question 14

cytochromes

Answer 14

an iron-containing protein that is a component of electron transport chains in the mitochondria and chloroplasts of eukaryotic cells and the plasma membranes of prokaryotic cells.

Question 15

ATP synthase

Answer 15

the enzyme that actually makes ATP from ADP and inorganic phosphate; in the inner membrane of the mitochondrion or prokaryotic plasma membrane.

Question 16

chemiosmosis

Answer 16

the process in which energy stored in the form of a hydrogen ion gradient across a membrane is used to drive cellular work sic as the synthesis of ATP.

Question 17

proton-motive force

Answer 17

the potential energy stored in the form of a proton electrochemical gradient, generated by the pumping of H+ ions across a biological membrane during chemiosmosis.

Question 18

alcohol fermentation

Answer 18

glycolysis followed by the reduction of pyruvate to ethyl alcohol, regenerating NAD+ and releasing carbon dioxide.

Question 19

lactic acid fermentation

Answer 19

glycolysis followed by the reduction of pyruvate to lactate, regenerating NAD+ w/ no release of carbon dioxide.

Question 20

obligate anaerobes

Answer 20

can only carry out fermentation or anaerobic respiration.

Question 21

facultative anaerobes

Answer 21

organisms that make enough ATP to survive using either fermentation or respiration.

Question 22

beta oxidation

Answer 22

a metabolic sequence that breaks fatty acids down to 2-C fragments that enter the citric acid cycle as acetyl CoA.