Catabolism: Energy Release and Conservation

Question 1

The total of all chemical reactions occurring in a cell is called \_\_\_\_\_\_\_\_.
A) anabolism
B) catabolism
C) metabolism
D) None of the choices are correct.

Answer 1

C

Question 2

Metabolic pathways can be either catabolic or anabolic but not both.

Answer 2

False

Question 3

________ pathways are those that function both catabolically and anabolically.

Answer 3

Amphibolic

Question 4

The catabolism of glucose begins with one or more of the glycolytic pathways that yield pyruvate.

Answer 4

True glycolysis

Question 5

________ ________ is a process that can completely catabolize an organic energy source to CO2 using the glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor for an electron transport chain.

Answer 5

Aerobic respiration

Question 6

Very few Gram-positive bacteria utilize the Entner-Doudoroff glycolytic pathway.

Answer 6

True almost none

Question 7

Some aerobic bacteria lack the Entner-Doudoroff and Embden-Meyerhoff pathways and instead use the pentose phosphate pathway for glycolysis.

Answer 7

False

Question 8

An organism may use glycolysis and the pentose phosphate pathway simultaneously.

Answer 8

True

Question 9

The net gain of ATP per molecule of glucose metabolized anaerobically via the Embden-Meyerhof pathway in prokaryotes is ________.

Answer 9

2 becuase no oxygen

Question 10

The net gain of ATP per molecule of glucose metabolized to pyruvate using Entner-Doudoroff pathway is ________.

Answer 10

1

Question 11

The pentose phosphate pathway produces \_\_\_\_\_\_\_\_.
A) CO2
B) NADPH
C) glyceraldehyde 3-phosphate
D) All of the choices are correct.

Answer 11

D

Question 12

The synthesis of ATP from ADP and Pi, when coupled with an exergonic chemical reaction is called \_\_\_\_\_\_\_\_ phosphorylation.
A) chemiosmotic
B) oxidative
C) substrate-level
D) conformational change

Answer 12

C

Question 13

) The most common pathway for conversion of glucose to pyruvate is \_\_\_\_\_\_\_\_.
A) Entner-Doudoroff
B) Pentose phosphate
C) Embden-Meyerhoff
D) mixed acid fermentation

Answer 13

C make sure not to confuse with A

Question 14

The TCA cycle generates all of the following from each acetyl-CoA molecule oxidized except \_\_\_\_\_\_\_\_.
A) three NADH molecules
B) two CO2 molecules
C) one FADH2 molecule
D) two ATP or GTP molecules

Answer 14

D

Question 15

The pyruvate dehydrogenase complex oxidizes and cleaves pyruvate to form one CO2 and \_\_\_\_\_\_\_\_.
A) lactate
B) isocitric acid
C) acetyl-CoA
D) succinyl-CoA

Answer 15

C

Question 16

After glycolysis, pyruvate is oxidized to one CO2 and the two-carbon molecule acetyl-CoA by a multienzyme system called the ________ ________ complex.

Answer 16

pyruvate dehydrogenase

Question 17

TCA cycle enzymes are found in the ________ ________ of eukaryotic cells

Answer 17

mitochondrial matrix

Krebs cycle

Question 18

In the TCA cycle, two carbons are removed from citric acid in the form of \_\_\_\_\_\_\_\_, thereby regenerating oxaloacetate to complete the cycle
A) acetyl-CoA
B) ethanol
C) carbon dioxide
D) methanol

Answer 18

C

Question 19

In the TCA cycle, two carbons in the form of \_\_\_\_\_\_\_\_ are added to oxaloacetate at the start of the cycle.
A) acetyl-CoA
B) ethanol
C) carbon dioxide
D) methanol

Answer 19

A

Question 20

The major function(s) of the TCA cycle is(are) ________.
A) energy production
B) provision of carbon skeletons for biosynthesis of cell components
C) electron transport
D) energy production and provision of carbon skeletons for biosynthesis of cell components

Answer 20

D

Question 21

When mitochondria pass electrons donated by NADH through the electron transport chain to molecular oxygen, a theoretical maximum of ________ molecules of ATP can be made per oxygen molecule reduced.

Answer 21

3

Question 22

The hypothesis that proton motive force drives ATP synthesis is called the ________ hypothesis.

Answer 22

chemiosmotic

Question 23

The most commonly accepted hypothesis for the production of ATP that results from electron transport system is called the ________ hypothesis.

Answer 23

chemiosmotic

Question 24

Bacterial electron transport chains may be comprised of fewer components and have lower phosphate to oxygen (P/O) ratios than mitochondrial transport chains.

Answer 24

True

Question 25

The electron transport systems in eukaryotes and prokaryotes use different electron carriers.

Answer 25

True

Question 26

In addition to being used in the making of ATP, a proton motive force is used directly to power the rotation of bacterial flagella

Answer 26

True

Question 27

Differences between mitochondrial and E. coli electron transport chains include which of the following?
A) The E. coli chain contains a different array of cytochromes.
B) The fundamental principles on which they operate are different.
C) Higher P/O values are observed in E. coli.
D) The electron transport chain does not involve membranes in E. coli.

Answer 27

A

Question 28

Which of the following is NOT true regarding ATP synthases?
A) They require proton motive force to make ATP.
B) They span the inner membrane of mitochondria.
C) The proton flow is outward during ATP synthesis.
D) The subunits of ATP synthase undergo conformational changes during ATP production.

Answer 28

C

Question 29

The theoretical maximum net gain of ATP per molecule of glucose metabolized aerobically in eukaryotes is \_\_\_\_\_\_\_\_.
A) 2
B) 32
C) 38
D) 85

Answer 29

C

Question 30

Production of ATP using the energy liberated when electrons from reduced chemical bonds are passed through the electron transport system is generally referred to as \_\_\_\_\_\_\_\_.
A) chemiosmotic
B) respiration
C) substrate-level
D) conformational change

Answer 30

B

Question 31

Mitochondrial electron transport takes place ________.
A) on the outer mitochondrial membrane
B) on the inner mitochondrial membrane
C) in the fluid matrix of the mitochondria
D) on the outer mitochondrial membrane and on the inner mitochondrial membrane

Answer 31

B

Question 32

In higher eukaryotes, most aerobically generated ATP is produced by ________.
A) glycolysis
B) the TCA cycle
C) a membrane-bound proton translocating ATP synthase during oxidative phosphorylation
D) All of the choices are correct.

Answer 32

C

Question 33

The number of ATP molecules generated per atom of oxygen that is reduced when electrons are passed from NADH or reduced FAD (FADH) to O2 is called the \_\_\_\_\_\_\_\_.
A) utilization ratio
B) energy yield
C) P/O ratio
D) phosphorylation coefficient

Answer 33

C

Question 34

In aerobic conditions, it takes ________ sugar to produce the same amount of ATP when compared to anaerobic conditions.

Answer 34

less

Question 35

Prokaryotes may use several different terminal oxidases for the electron transport system.

Answer 35

True

Question 36

Which of the following can be used as electron acceptors during anaerobic respiration?
A) Nitrate
B) Sulfate
C) Carbon dioxide
D) All of the choices are correct.

Answer 36

D

Question 37

Organisms that form lactate, ethanol, and CO2 as end products of glucose metabolism are called ________ fermenters.

Answer 37

heterolactic

Question 38

Fermentation involves the use of pyruvate and/or other organic molecules as electron acceptors.

Answer 38

True

Question 39

In the process of fermentation an organic substrate, such as glucose, is reduced and an intermediate of the pathway, such as pyruvate, is oxidized.

Answer 39

False

Question 40

Oxygen is always required for the regeneration of NAD from NADH.

Answer 40

False

Question 41

Large external polysaccharides are degraded by bacteria and archaea using ________ ________, which they secrete outside the cell.

Answer 41

hydrolytic enzymes

Question 42

Disaccharides and polysaccharides can be processed as nutrients after first being cleaved to monosaccharides by either ________ or ________.

Answer 42

hydrolysis; phosphorolysis

Question 43

Fatty acids are metabolized by the \_\_\_\_\_\_\_\_ pathway.
A) alpha-oxidation
B) beta-oxidation
C) gamma-oxidation
D) delta-oxidation

Answer 43

B

Question 44

During breakdown of fatty acids, carbons are removed \_\_\_\_\_\_\_\_ at a time with each turn of the cycle, and two carbon units are released as \_\_\_\_\_\_\_\_.
A) one; carbon dioxide
B) one; methane
C) two; acetyl-CoA
D) two; ethanol

Answer 44

C 2-acetyl CoA

Question 45

Proteins are catabolized by hydrolytic cleavage to amino acids by the action of enzymes called ________.

Answer 45

proteases

Question 46

Amino acids are processed first by the removal of the amino group through \_\_\_\_\_\_\_\_.
A) deamination
B) transamination
C) phosphorolytic cleavage
D) deamination or transamination

Answer 46

D

Question 47

________ is a two-step process that depends on the activity of at least two genera to carry out the oxidation of ammonia to nitrate.

Answer 47

Nitrification

Question 48

Which of the following may be used as sources of energy by chemolithotrophs?
A) Hydrogen gas
B) Reduced nitrogen compounds
C) Reduced sulfur compounds
D) All of the choices are correct.

Answer 48

D

Question 49

How many molecules of ATP are needed to reduce one molecule of carbon dioxide to carbohydrate by oxygenic phototrophs during the dark reactions of photosynthesis?
A) 2
B) 3
C) 4
D) 10–12

Answer 49

B—3

Question 50

How many molecules of NADPH are needed to reduce one molecule of carbon dioxide to carbohydrate by oxygenic phototrophs during the dark reactions of photosynthesis?
A) 2
B) 3
C) 4
D) 10–12

Answer 50

A–2

Question 51

How many quanta of light are needed to reduce one molecule of carbon dioxide to carbohydrate during photosynthesis?
A) 2
B) 3
C) 4
D) 10–12

Answer 51

D