Question 1

The corrin ring is very similar to a heme,but the corrin ring containing vitamin B12 has a cobalt ion rather than an iron ion as in heme.

Accepted Answer

A) True 
 B)False

Question 2

Which in not a lipid-soluble vitamin?

Accepted Answer

A) A 
B) C 
C) E 
D) K 
A) A 
B) C 
C) E 
D) K

Question 3

All enzymes require metallic cations to achieve full catalytic activity.

Accepted Answer

A) True 
 B)False

Question 4

Vitamin E is formed non-enzymatically in sun-exposed skin.

Accepted Answer

A) True 
 B)False

Question 5

Vitamin C is not a coenzyme but acts in cell metabolism as a

Accepted Answer

A) buffer. 
B) source of glucose. 
C) reducing agent. 
D) key nutrient. 
A) buffer. 
B) source of glucose. 
C) reducing agent. 
D) key nutrient.

Question 6

The "+" sign in NAD+ indicates that

Accepted Answer

A) this is the reduced form of the coenzyme. 
B) the nitrogen atom has a positive charge. 
C) the entire molecule is positively charged. 
D) it can bind to negatively charged proteins only. 
A) this is the reduced form of the coenzyme. 
B) the nitrogen atom has a positive charge. 
C) the entire molecule is positively charged. 
D) it can bind to negatively charged proteins only.

Question 7

Which coenzyme is likely involved in the reaction shown below?

Accepted Answer

A) TPP. 
B) Biotin. 
C) Coenzyme A. 
D) FMN. 
A) TPP. 
B) Biotin. 
C) Coenzyme A. 
D) FMN.

Question 8

Structures of several dehydrogenases indicate that many possess one or more similar NAD or NADP-binding structures consisting of babab units in Rossman folds.

Accepted Answer

A) True 
 B)False

Question 9

Match each of the following vitamins with an associate nutritional deficiency disease.
-Cobalamin (B12)

Accepted Answer

A) Pernicious anemia 
B) anemia 
C) Dermititis in humans 
D) scurvy 
E) beriberi 
A) Pernicious anemia 
B) anemia 
C) Dermititis in humans 
D) scurvy 
E) beriberi

Question 10

ATP is involved in

Accepted Answer

A) transferring a phosphate group to other compounds. 
B) forming S-adenosylmethionine. 
C) transfer of its AMP moiety to another compound. 
D) All of the above. 
E) A and C only. 
A) transferring a phosphate group to other compounds. 
B) forming S-adenosylmethionine. 
C) transfer of its AMP moiety to another compound. 
D) All of the above. 
E) A and C only.

Question 11

There is little risk in taking megadoses of vitamin A since excess will tend to simply be excreted in the urine.

Accepted Answer

A) True 
 B)False

Question 12

Which is the strongest oxidizing agent?

Accepted Answer

A) Ubiquinone. 
B) NAD+. 
C) FMN. 
D) Vitamin K. 
A) Ubiquinone. 
B) NAD+. 
C) FMN. 
D) Vitamin K.

Question 13

Lysine can join the prosthetic group biotin to an enzyme via an amide link at the ε-amino group.

Accepted Answer

A) True 
 B)False

Question 14

Mammalian cells can synthesize all needed coenzymes from simple precursors.

Accepted Answer

A) True 
 B)False

Question 15

Rickets in children and osteomalacia in adults is caused by a lack of ________.

Accepted Answer

A) thiamin 
B) hemoglobin 
C) vitamin D 
D) vitamin B12 
A) thiamin 
B) hemoglobin 
C) vitamin D 
D) vitamin B12

Question 16

An ion commonly found in metalloenzymes and which can undergo reversible oxidation and reduction is

Accepted Answer

A) Ca++. 
B) Mg++. 
C) S-. 
D) Fe++. 
E) All of the above. 
A) Ca++. 
B) Mg++. 
C) S-. 
D) Fe++. 
E) All of the above.

Question 17

The oxidized forms of cytochromes c absorbs more strongly than the reduced form at the Soret band near 400 nm.

Accepted Answer

A) True 
 B)False

Question 18

Active holoenzymes are formed from ________ in the presence of ________.

Accepted Answer

A) cofactors;proteins 
B) proteins;cofactors 
C) apoenzymes;cofactors 
D) apoenzymes;proteins 
E) apoenzymes;inactive holoenzymes 
A) cofactors;proteins 
B) proteins;cofactors 
C) apoenzymes;cofactors 
D) apoenzymes;proteins 
E) apoenzymes;inactive holoenzymes

Question 19

Enzymes with vitamin B₆ as the prosthetic group catalyze a variety of reactions involving

Accepted Answer

A) lipids. 
B) sugars. 
C) amino acids. 
D) other vitamins. 
A) lipids. 
B) sugars. 
C) amino acids. 
D) other vitamins.

Question 20

Match each of the following vitamins with an associate nutritional deficiency disease.
-Biotin

Accepted Answer

A) Pernicious anemia 
B) anemia 
C) Dermititis in humans 
D) scurvy 
E) beriberi 
A) Pernicious anemia 
B) anemia 
C) Dermititis in humans 
D) scurvy 
E) beriberi

Exam 7: Coenzymes and Vitamins

The corrin ring is very similar to a heme,but the corrin ring containing vitamin B12 has a cobalt ion rather than an iron ion as in heme.

Which in not a lipid-soluble vitamin?

All enzymes require metallic cations to achieve full catalytic activity.

Vitamin E is formed non-enzymatically in sun-exposed skin.

Vitamin C is not a coenzyme but acts in cell metabolism as a

The "+" sign in NAD+ indicates that

Which coenzyme is likely involved in the reaction shown below?

Structures of several dehydrogenases indicate that many possess one or more similar NAD or NADP-binding structures consisting of babab units in Rossman folds.

Match each of the following vitamins with an associate nutritional deficiency disease. -Cobalamin (B12)

ATP is involved in

There is little risk in taking megadoses of vitamin A since excess will tend to simply be excreted in the urine.

Which is the strongest oxidizing agent?

Lysine can join the prosthetic group biotin to an enzyme via an amide link at the ε-amino group.

Mammalian cells can synthesize all needed coenzymes from simple precursors.

Rickets in children and osteomalacia in adults is caused by a lack of ________.

An ion commonly found in metalloenzymes and which can undergo reversible oxidation and reduction is

The oxidized forms of cytochromes c absorbs more strongly than the reduced form at the Soret band near 400 nm.

Active holoenzymes are formed from ________ in the presence of ________.

Enzymes with vitamin B₆ as the prosthetic group catalyze a variety of reactions involving

Match each of the following vitamins with an associate nutritional deficiency disease. -Biotin

Introduction to Biochemistry

Water

Amino Acids and the Primary Structures of Proteins

Proteins: Three-Dimensional Structure and Function

Properties of Enzymes

Mechanisms of Enzymes

Carbohydrates

Lipids and Membranes

Introduction to Metabolism

Glycolysis

Gluconeogenesis, the Pentose Phosphate Pathway, and Glycogen Metabolism

The Citric Acid Cycle

Electron Transport and Atp Synthesis

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Nucleic Acids

DNA Replication, repair, and Recombination

Transcription and RNA Processing

Protein Synthesis

Filters

Match each of the following vitamins with an associate nutritional deficiency disease. -Cobalamin (B₁₂)

Active holoenzymes are formed from in the presence of .