Question 1

Vitamin C is a vitamin but not a coenzyme because it

Accepted Answer

A) does not bind to proteins. 
B) is a prosthetic group. 
C) is a reducing agent during hydroxylation of collagen. 
D) is not required in human diets. 
A) does not bind to proteins. 
B) is a prosthetic group. 
C) is a reducing agent during hydroxylation of collagen. 
D) is not required in human diets.

Question 2

Lipid vitamins such as A,D,E,and K are stored by animal cells,so excessive daily intake may be toxic.

Accepted Answer

A) True 
 B)False

Question 3

What structure is shown?

Accepted Answer

A) NADH 
B) NAD+ 
C) FMN 
D) FAD 
A) NADH 
B) NAD+ 
C) FMN 
D) FAD

Question 4

Protein catalysts rely exclusively on the amino acid residues for reactivity at the sites of action.

Accepted Answer

A) True 
 B)False

Question 5

Which functional group is shown below?

Accepted Answer

A) Schiff base. 
B) Secondary amine. 
C) Amide. 
D) Peptide bond. 
A) Schiff base. 
B) Secondary amine. 
C) Amide. 
D) Peptide bond.

Question 6

Which is the largest B vitamin?

Accepted Answer

A) B1 
B) B6 
C) B8 
D) B12 
A) B1 
B) B6 
C) B8 
D) B12

Question 7

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

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 8

The metal ions in metalloenzymes are firmly bound at the active site of the enzyme.The ion may be bound to side chains of amino acids or may be part of a ________ group such as those found in catalase and cytochromes.

Accepted Answer

A) sulfur clusters 
B) phosphate 
C) vitamin 
D) heme 
A) sulfur clusters 
B) phosphate 
C) vitamin 
D) heme

Question 9

Which substance would make a good ligand for biotin on the matrix of an affinity chromatography column?

Accepted Answer

A) Ubiquinone. 
B) Avidin. 
C) Oxaloacetate. 
D) Any molecule with an -SH group. 
A) Ubiquinone. 
B) Avidin. 
C) Oxaloacetate. 
D) Any molecule with an -SH group.

Question 10

Pernicious anemia is caused by a deficiency in biotin.

Accepted Answer

A) True 
 B)False

Question 11

Unlike NADH and NADPH,FAD and FADH₂

Accepted Answer

A) donate one electron at a time. 
B) donate one or two electrons at a time. 
C) do not become positively charged. 
D) A and C. 
E) B and C. 
A) donate one electron at a time. 
B) donate one or two electrons at a time. 
C) do not become positively charged. 
D) A and C. 
E) B and C.

Question 12

Which coenzyme links to a lysine residue in a protein's active site?

Accepted Answer

A) Biotin. 
B) Lipoic acid (lipoamide). 
C) pyridoxal phosphate. 
D) Biotin and pyridoxal phosphate only. 
E) All three;biotin,lipoic acid and pyridoxal phosphate. 
A) Biotin. 
B) Lipoic acid (lipoamide). 
C) pyridoxal phosphate. 
D) Biotin and pyridoxal phosphate only. 
E) All three;biotin,lipoic acid and pyridoxal phosphate.

Question 13

The product(s)of lactate dehydrogenase under anaerobic conditions in the muscle is (are)

Accepted Answer

A) pyruvic acid. 
B) NAD+. 
C) NADH. 
D) A and B. 
E) A and C. 
A) pyruvic acid. 
B) NAD+. 
C) NADH. 
D) A and B. 
E) A and C.

Question 14

Vitamin C is a coenzyme during the hydroxylation of collagen.

Accepted Answer

A) True 
 B)False

Question 15

TPP is a(n)________ of yeast pyruvate decarboxylase.

Accepted Answer

A) cosubstrate 
B) intrinsic factor 
C) metalloenzyme 
D) prosthetic group 
A) cosubstrate 
B) intrinsic factor 
C) metalloenzyme 
D) prosthetic group

Question 16

Which amino acid can form a covalent bond to the coenzyme pyridoxal phosphate?

Accepted Answer

A) Aspartate. 
B) Cysteine. 
C) Lysine. 
D) Serine. 
E) All of the above. 
A) Aspartate. 
B) Cysteine. 
C) Lysine. 
D) Serine. 
E) All of the above.

Question 17

Which statement is false about plastoquinone?

Accepted Answer

A) It is water soluble. 
B) It is important in photosynthetic electron transport. 
C) It contains five-carbon isoprenoid units. 
D) It can be converted to a semiquinone form. 
A) It is water soluble. 
B) It is important in photosynthetic electron transport. 
C) It contains five-carbon isoprenoid units. 
D) It can be converted to a semiquinone form.

Question 18

Metalloenzymes contain metal ions which are bound tightly to the protein and can attract electrons.

Accepted Answer

A) True 
 B)False

Question 19

Vitamin A is produced from β-carotene by a condensation reaction.

Accepted Answer

A) True 
 B)False

Question 20

Which would be an efficient method of purifying biotin?

Accepted Answer

A) Affinity chromatography on a column of immobilized avidin. 
B) SDS-PAGE with avidin uniformly dispersed in the gel. 
C) Precipitation of biotin using amylopectin. 
D) Site-directed mutagenesis using avidin as the mutating agent. 
A) Affinity chromatography on a column of immobilized avidin. 
B) SDS-PAGE with avidin uniformly dispersed in the gel. 
C) Precipitation of biotin using amylopectin. 
D) Site-directed mutagenesis using avidin as the mutating agent.

Exam 7: Coenzymes and Vitamins

Vitamin C is a vitamin but not a coenzyme because it

Lipid vitamins such as A,D,E,and K are stored by animal cells,so excessive daily intake may be toxic.

What structure is shown?

Protein catalysts rely exclusively on the amino acid residues for reactivity at the sites of action.

Which functional group is shown below?

Which is the largest B vitamin?

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

The metal ions in metalloenzymes are firmly bound at the active site of the enzyme.The ion may be bound to side chains of amino acids or may be part of a ________ group such as those found in catalase and cytochromes.

Which substance would make a good ligand for biotin on the matrix of an affinity chromatography column?

Pernicious anemia is caused by a deficiency in biotin.

Unlike NADH and NADPH,FAD and FADH₂

Which coenzyme links to a lysine residue in a protein's active site?

The product(s)of lactate dehydrogenase under anaerobic conditions in the muscle is (are)

Vitamin C is a coenzyme during the hydroxylation of collagen.

TPP is a(n)________ of yeast pyruvate decarboxylase.

Which amino acid can form a covalent bond to the coenzyme pyridoxal phosphate?

Which statement is false about plastoquinone?

Metalloenzymes contain metal ions which are bound tightly to the protein and can attract electrons.

Vitamin A is produced from β-carotene by a condensation reaction.

Which would be an efficient method of purifying 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

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