Question 1

5-Fluorouracil is an anticancer drug that inhibits what essential enzyme?

Accepted Answer

Thymidylate synthase

Question 2

What are the products obtained from the reaction of NADH with FMN catalyzed by NADH dehydrogenase as shown below?

Accepted Answer

A) NAD+ + FMNH2 
B) NAD+ + FMNH 
C) NAF + DHN 
D) NAF + DNH2 
E) N2A2D2 + FMNH2 
A) NAD+ + FMNH2 
B) NAD+ + FMNH 
C) NAF + DHN 
D) NAF + DNH2 
E) N2A2D2 + FMNH2 A

Question 3

Which of the following vitamins can be synthesized by all mammals except humans and guinea pigs?

Accepted Answer

A) vitamin B12 
B) riboflavin (B2) 
C) vitamin C 
D) thiamine (B1) 
E) pyridoxine (B6) 
A) vitamin B12 
B) riboflavin (B2) 
C) vitamin C 
D) thiamine (B1) 
E) pyridoxine (B6) C

Question 4

All water-soluble vitamins except vitamin ________ are precursors of coenzymes.

Accepted Answer

A) C 
B) K 
C) D 
D) B1 
E) B12 
A) C 
B) K 
C) D 
D) B1 
E) B12

Question 5

Which of the following is/are the coenzyme(s)formed from the vitamin thiamine (B1)?

Accepted Answer

A) TPP 
B) CoASH 
C) PLP 
D) THF 
E) FAD 
A) TPP 
B) CoASH 
C) PLP 
D) THF 
E) FAD

Question 6

Which of the following vitamins catalyzes one-carbon transfer reactions and requires THF as a coenzyme?

Accepted Answer

A) biotin 
B) thiamine 
C) folic acid 
D) ascorbic acid 
E) panthothenate 
A) biotin 
B) thiamine 
C) folic acid 
D) ascorbic acid 
E) panthothenate

Question 7

Identify all group(s)that tetrahydrofolate transfers.

Accepted Answer

A) methylene 
B) methyl 
C) ethyl 
D) formyl 
E) A,B,and D 
A) methylene 
B) methyl 
C) ethyl 
D) formyl 
E) A,B,and D

Question 8

Explain what is meant by a prosthetic group.Give an example.

Accepted Answer

A tightly bound coenzyme is kn

Question 9

Give the product for the following reaction.

Accepted Answer

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

Question 10

Which of the following is not needed for the pyruvate dehydrogenase system?

Accepted Answer

A) lipoate 
B) coenzyme A 
C) FAD 
D) NAD+ 
E) biotin 
A) lipoate 
B) coenzyme A 
C) FAD 
D) NAD+ 
E) biotin

Question 11

Which molecule does the following structure represent?

Accepted Answer

A) coenzyme A 
B) thiamine 
C) pyruvate 
D) NADPH 
E) biotin 
A) coenzyme A 
B) thiamine 
C) pyruvate 
D) NADPH 
E) biotin

Question 12

Which of the following substrates requires the coenzyme thiamine pyrophosphate (TPP)for catalyzing its decarboxylation reaction?

Accepted Answer

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

Question 13

The common name of vitamin B1 is

Accepted Answer

A) niacin. 
B) riboflavin. 
C) thiamine. 
D) biotin. 
E) panthothenate. 
A) niacin. 
B) riboflavin. 
C) thiamine. 
D) biotin. 
E) panthothenate.

Question 14

Give the purpose of vitamin KH2 as a coenzyme.

Accepted Answer

A) catalyzes the carboxylation of the alpha-carbon of the glutamate side chain in proteins 
B) catalyzes the carboxylation of the beta-carbon of the glutamate side chain in proteins 
C) catalyzes the carboxylation of the beta-carbon of the aspartate side chain in proteins 
D) catalyzes the carboxylation of the gamma-carbon of the glutamate side chain in proteins 
E) catalyzes the carboxylation of the alpha-carbon of the aspartate side chain in proteins 
A) catalyzes the carboxylation of the alpha-carbon of the glutamate side chain in proteins 
B) catalyzes the carboxylation of the beta-carbon of the glutamate side chain in proteins 
C) catalyzes the carboxylation of the beta-carbon of the aspartate side chain in proteins 
D) catalyzes the carboxylation of the gamma-carbon of the glutamate side chain in proteins 
E) catalyzes the carboxylation of the alpha-carbon of the aspartate side chain in proteins

Question 15

Explain why a cell typically maintains its [NAD+]/[NADH] ratio near 1000 while keeping its [NADP+]/[NADPH] ratio at about 0.01.

Accepted Answer

The relative concentrations of coenzymes

Question 16

What is the first reaction in the catabolism of most amino acids?

Accepted Answer

A) transamination 
B) decarboxylation 
C) phosphorylation 
D) aldolation 
E) ligation 
A) transamination 
B) decarboxylation 
C) phosphorylation 
D) aldolation 
E) ligation

Question 17

Which of the following best represents the chemical reaction catalyzed by B12-dependent enzymes?

Accepted Answer

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

Question 18

Give the product for the following reaction.

Accepted Answer

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

Question 19

Which of the following statements regarding glycolysis is correct?

Accepted Answer

A) Glycolysis is another name for the Krebs cycle. 
B) Disaccharides can enter glycolysis without being hydrolyzed. 
C) Glycolysis occurs primarily in the fluid outside the cell. 
D) Glycolysis is the series of reactions which produces 2 moles of pyruvate from each mole of D-glucose. 
E) Glycolysis is the series of reactions which is responsible for the complete oxidation of pyruvate and acetyl-CoA to carbon dioxide. 
A) Glycolysis is another name for the Krebs cycle. 
B) Disaccharides can enter glycolysis without being hydrolyzed. 
C) Glycolysis occurs primarily in the fluid outside the cell. 
D) Glycolysis is the series of reactions which produces 2 moles of pyruvate from each mole of D-glucose. 
E) Glycolysis is the series of reactions which is responsible for the complete oxidation of pyruvate and acetyl-CoA to carbon dioxide.

Question 20

Explain what is meant by a nucleotide and give an example.

Accepted Answer

A nucleotide is composed of a heterocycl

Exam 23: The Organic Chemistry of the Coenzymes, compounds Derived From Vitamins

5-Fluorouracil is an anticancer drug that inhibits what essential enzyme?

What are the products obtained from the reaction of NADH with FMN catalyzed by NADH dehydrogenase as shown below?

Which of the following vitamins can be synthesized by all mammals except humans and guinea pigs?

All water-soluble vitamins except vitamin ________ are precursors of coenzymes.

Which of the following is/are the coenzyme(s)formed from the vitamin thiamine (B1)?

Which of the following vitamins catalyzes one-carbon transfer reactions and requires THF as a coenzyme?

Identify all group(s)that tetrahydrofolate transfers.

Explain what is meant by a prosthetic group.Give an example.

Give the product for the following reaction.

Which of the following is not needed for the pyruvate dehydrogenase system?

Which molecule does the following structure represent?

Which of the following substrates requires the coenzyme thiamine pyrophosphate (TPP)for catalyzing its decarboxylation reaction?

The common name of vitamin B1 is

Give the purpose of vitamin KH2 as a coenzyme.

Explain why a cell typically maintains its [NAD+]/[NADH] ratio near 1000 while keeping its [NADP+]/[NADPH] ratio at about 0.01.

What is the first reaction in the catabolism of most amino acids?

Which of the following best represents the chemical reaction catalyzed by B12-dependent enzymes?

Give the product for the following reaction.

Which of the following statements regarding glycolysis is correct?

Explain what is meant by a nucleotide and give an example.

Remembering General Chemistry: Electronic Structure and Bonding

Acids and Bases: Central to Understanding Organic Chemistry

An Introduction to Organic Compounds: Nomenclature, physical Properties, and Structure

Isomers: the Arrangement of Atoms in Space

Alkenes: Structure,nomenclature,and an Introduction to Reactivity - Thermodynamics and Kinetics

The Reactions of Alkenes - the Stereochemistry of Addition Reactions

The Reactions of Alkynes - Introduction to Multistep Synthesis

Delocalized Electrons: Their Effect on Stability, pka, and the Products of a Reaction - Aromaticity and Electronic Effects: an Introduction to the Reactions of Benzene

Substitution and Elimination Reactions of Alkyl Halides

Reactions of Alcohols, ethers, epoxides, amines and Sulfur-Containing Compounds

Organometallic Compounds

Radicals

Mass Spectrometry,infrared Spectroscopy,and Uvvis Spectroscopy

Nmr Spectroscopy

Reactions of Carboxylic Acids and Carboxylic Acid Derivatives

Reactions of Aldehydes and Ketones

Reactions at the Α-Carbon

Reactions of Benzene and Substituted Benzenes

More About Amines - Reactions of Heterocylic Compounds

The Organic Chemistry of Carbohydrates

Amino Acids,peptides,and Proteins

Catalysis in Organic Reactions and in Enzymatic Reactions

The Organic Chemistry of the Metabolic Pathways

The Organic Chemistry of Lipids

The Chemistry of the Nucleic Acids

Synthetic Polymers

Pericyclic Reactions

Filters

Which of the following is/are the coenzyme(s)formed from the vitamin thiamine (B₁)?

The common name of vitamin B₁ is

Give the purpose of vitamin KH₂ as a coenzyme.

Explain why a cell typically maintains its [NAD⁺]/[NADH] ratio near 1000 while keeping its [NADP⁺]/[NADPH] ratio at about 0.01.

Which of the following best represents the chemical reaction catalyzed by B₁₂-dependent enzymes?