Question 1

Long hydrocarbon chains (> C20) are more readily catabolized than are shorter hydrocarbon chains.

Accepted Answer

A) True 
 B)False

Question 2

Inorganic arsenic compounds can serve as electron acceptors for anaerobic respiration.

Accepted Answer

A) True 
 B)False

Question 3

Explain from a biochemical standpoint why the odor that results from putrefaction is mainly a result of clostridial activity.

Accepted Answer

The answer of Explain from a biochemical standpoint why the...

Question 4

Electrons for the reduction of CO2 to CH4 come mainly from

Accepted Answer

A)  glucose. 
B)  H2. 
C)  CO2. 
D)  ferric iron.

Question 5

_________is a process in which some molecules of a substrate are oxidized while some are reduced.

Accepted Answer

The answer of _________is a process in which some molecules...

Question 6

Which of the following is NOT a characteristic of syntrophy?

Accepted Answer

A)  Most are secondary fermentations. 
B)  The free energy change for the second reaction is positive. 
C)  The net ATP yields are often low. 
D)  It requires several different organisms.

Question 7

When facultative anaerobes are exposed to oxygen, they

Accepted Answer

A)  modify their gene expression to favor aerobic metabolism and downregulate anaerobic metabolism genes. 
B)  undergo both aerobic and anaerobic pathways simultaneously to maximize energy yields. 
C)  primarily manipulate enzyme activities through biochemical reactions. 
D)  perform both A and B.

Question 8

Redox balance is achieved in fermentation by the production of

Accepted Answer

A)  molecular hydrogen. 
B)  electrons. 
C)  molecular oxygen. 
D)  acids.

Question 9

Which product(s) is/are formed from the disproportionation of thiosulfate?

Accepted Answer

A)  an oxidized sulfate and a reduced hydrogen sulfide 
B)  two sulfonates 
C)  two thiolate ions 
D)  an oxidized thiolate and a reduced sulfonate

Question 10

A minimal requirement for an energy- conserving reaction is that it must yield sufficient free energy to_________ .

Accepted Answer

The answer of A minimal requirement for an energy- conserving...

Question 11

The most oxidized form of sulfur is

Accepted Answer

A)  dihydrogen sulfide. 
B)  sulfur hydride. 
C)  sulfate. 
D)  sulfite.

Question 12

Enzymes that catalyze incorporation of both oxygen atoms from O2 into organic compounds are called_________ , and enzymes that incorporate one of the two oxygen atoms from O2 into organic compounds are called_________ .

Accepted Answer

The answer of Enzymes that catalyze incorporation of both oxygen...

Question 13

Bacteria such as Dehalococcoides, which reductively dechloronate toxic compounds such as polychlorinated biphenyls (PCBs), are attractive for bioremediation efforts.

Accepted Answer

A) True 
 B)False

Question 14

Complete oxidation of fatty acids yields

Accepted Answer

A)  NAD+ or NADP+. 
B)  acetyl- CoA. 
C)  electron pairs. 
D)  CH4.

Question 15

_________is the situation in which two different organisms can together degrade some substances that neither could degrade separately.

Accepted Answer

The answer of _________is the situation in which two different...

Question 16

The first step of dissimilative nitrate reduction involves

Accepted Answer

A)  nitrite reductase. 
B)  nitrite oxidase. 
C)  nitrate reductase. 
D)  nitrate oxidase.

Question 17

The oxidation- reduction balance referred to when discussing redox reactions is theoretical rather than real because the numbers of protons and electrons do not necessarily match.

Accepted Answer

A) True 
 B)False

Question 18

While some aerobic bacteria are capable of growth on acetate as a sole carbon source, many anaerobic bacteria produce acetate during __________.

Accepted Answer

The answer of While some aerobic bacteria are capable of...

Question 19

Anoxic degradation of aliphatic and aromatic hydrocarbons use oxygen in the form of_________rather than molecular oxygen (gas) to begin catabolism.

Accepted Answer

The answer of Anoxic degradation of aliphatic and aromatic hydrocarbons...

Question 20

In terms of oxygen requirements, homoacetogens and methanogens are

Accepted Answer

A)  strict anaerobes. 
B)  facultative anaerobes. 
C)  facultative aerobes. 
D)  strict aerobes.

Exam 14: Catabolism of Organic Compounds

Long hydrocarbon chains (> C₂₀) are more readily catabolized than are shorter hydrocarbon chains.

Inorganic arsenic compounds can serve as electron acceptors for anaerobic respiration.

Explain from a biochemical standpoint why the odor that results from putrefaction is mainly a result of clostridial activity.

Electrons for the reduction of CO₂ to CH₄ come mainly from

_________is a process in which some molecules of a substrate are oxidized while some are reduced.

Which of the following is NOT a characteristic of syntrophy?

When facultative anaerobes are exposed to oxygen, they

Redox balance is achieved in fermentation by the production of

Which product(s) is/are formed from the disproportionation of thiosulfate?

A minimal requirement for an energy- conserving reaction is that it must yield sufficient free energy to_________ .

The most oxidized form of sulfur is

Enzymes that catalyze incorporation of both oxygen atoms from O2 into organic compounds are called_ , and enzymes that incorporate one of the two oxygen atoms from O2 into organic compounds are called_ .

Bacteria such as Dehalococcoides, which reductively dechloronate toxic compounds such as polychlorinated biphenyls (PCBs), are attractive for bioremediation efforts.

Complete oxidation of fatty acids yields

_________is the situation in which two different organisms can together degrade some substances that neither could degrade separately.

The first step of dissimilative nitrate reduction involves

The oxidation- reduction balance referred to when discussing redox reactions is theoretical rather than real because the numbers of protons and electrons do not necessarily match.

While some aerobic bacteria are capable of growth on acetate as a sole carbon source, many anaerobic bacteria produce acetate during __________.

Anoxic degradation of aliphatic and aromatic hydrocarbons use oxygen in the form of_________rather than molecular oxygen (gas) to begin catabolism.

In terms of oxygen requirements, homoacetogens and methanogens are