TEST BANK FOR BIOCHEMISTRY
QUESTIONS AND ANSWERS 2024/2025
Chapter 3--Amino Acids and Peptides Key
1. The amino and carboxyl groups of amino acids are bonded to which carbon?
A. Both are bonded to the a-carbon.
B. Both are bonded to the b-carbon.
C. The amino is bonded to the a-carbon, and the carboxyl is bonded to the b-carbon. D. The
amino is bonded to the b-carbon, and the carboxyl is bonded to the a-carbon.
2. The side chain groups of amino acids are bonded to which carbon?
A. The a-carbon.
B. The b-carbon.
C. The carbonyl carbon.
D. Different amino acids have their side chains attached to different carbons.
3. Chiral objects
A. are cyclic compounds in the chair form.
B. are not superimposable on their mirror images. C. never occur in nature.
D. do not form crystals.
4. Which of the following has no L or D configuration? A. Glyceraldehyde
B. Proline
C. Glycine
D. All of these have an L or D configuration
5. The absolute configuration of amino acids are denoted by their relationship to the L- or D-
forms of A. glyceraldehyde
B. glucose
C. tartaric acid
D. alanine
6. The amino acids which occur in proteins A. are all of the L- form.
B. are all of the D- form.
C. can be either the L- or D- form.
D. do not have L- and D- forms.
,7. Which of the following is an amino acid not found in proteins? A. asparagine
B. ornithine
C. isoleucine
D. proline
,8. Which amino acid has the one-letter symbol E? A. lysine
B. phenylalanine
C. histidine
D. glutamic acid
9. Which amino acid has the three-letter symbol asn? A. aspartic acid
B. asparagine
C. alanine
D. arginine
10. Which is a correct pair of abbreviations for an amino acid? A. Gln / N
B. Tyr / T
C.Asn / N
D. Phe / P E. Pro / Q
11. Which amino acid has a benzene-like ring? A. Glutamic Acid
B. Histidine
C. Isoleucine
D. Serine E. Tyrosine
12. Which amino acid is classified as polar? A. L
B. H
C. P
D. I
13. Which group consists only of amino acids with polar side chains? A. serine, threonine, and
leucine
B. serine, threonine, and cysteine
C. serine, threonine, and valine
D. serine, threonine, and isoleucine
14. Which of the following has a hydrophilic side chain?
A. Asn B. Leu C. Ile D. Gly
15. Which of the following amino acids has a side chain that can make hydrogen bonds to other
molecules? A. Leu
B. Ser
C. Ala
, D. Gly
16. Asp and Glu both have amides as side chains. A. True
B. False
17. Thr and Ser both have hydroxyls as side chains. A. True
B. False
18. The side chain of Met is a poor hydrogen bond donor. A. True
B. False
19. Which group consists only of amino acids with carboxylate side chains? A. glutamate and
cysteine
B. aspartate and glycine
C. glutamate and lysine
D. aspartate and glutamate
20. Which group consists only of amino acids with basic side chains? A. leucine and lysine
B. arginine and leucine
C. lysine and arginine
D. arginine and isoleucine
21. Which amino acids contain sulfur? A. cysteine and lysine
B. cysteine and methionine
C. arginine and methionine
D. cysteine and isoleucine
22. Which amino acid takes on a negative charge when the R-group loses a proton? A. Glutamic
Acid
B. Histidine
C. Glutamine
D. Tyrosine
E. Glutamic Acid and Tyrosine
23. Which amino acid takes on a positive charge when the R-group gains a proton? A. Glutamic
Acid
B. Histidine
C. Glutamine
D. Tyrosine E. Glycine
QUESTIONS AND ANSWERS 2024/2025
Chapter 3--Amino Acids and Peptides Key
1. The amino and carboxyl groups of amino acids are bonded to which carbon?
A. Both are bonded to the a-carbon.
B. Both are bonded to the b-carbon.
C. The amino is bonded to the a-carbon, and the carboxyl is bonded to the b-carbon. D. The
amino is bonded to the b-carbon, and the carboxyl is bonded to the a-carbon.
2. The side chain groups of amino acids are bonded to which carbon?
A. The a-carbon.
B. The b-carbon.
C. The carbonyl carbon.
D. Different amino acids have their side chains attached to different carbons.
3. Chiral objects
A. are cyclic compounds in the chair form.
B. are not superimposable on their mirror images. C. never occur in nature.
D. do not form crystals.
4. Which of the following has no L or D configuration? A. Glyceraldehyde
B. Proline
C. Glycine
D. All of these have an L or D configuration
5. The absolute configuration of amino acids are denoted by their relationship to the L- or D-
forms of A. glyceraldehyde
B. glucose
C. tartaric acid
D. alanine
6. The amino acids which occur in proteins A. are all of the L- form.
B. are all of the D- form.
C. can be either the L- or D- form.
D. do not have L- and D- forms.
,7. Which of the following is an amino acid not found in proteins? A. asparagine
B. ornithine
C. isoleucine
D. proline
,8. Which amino acid has the one-letter symbol E? A. lysine
B. phenylalanine
C. histidine
D. glutamic acid
9. Which amino acid has the three-letter symbol asn? A. aspartic acid
B. asparagine
C. alanine
D. arginine
10. Which is a correct pair of abbreviations for an amino acid? A. Gln / N
B. Tyr / T
C.Asn / N
D. Phe / P E. Pro / Q
11. Which amino acid has a benzene-like ring? A. Glutamic Acid
B. Histidine
C. Isoleucine
D. Serine E. Tyrosine
12. Which amino acid is classified as polar? A. L
B. H
C. P
D. I
13. Which group consists only of amino acids with polar side chains? A. serine, threonine, and
leucine
B. serine, threonine, and cysteine
C. serine, threonine, and valine
D. serine, threonine, and isoleucine
14. Which of the following has a hydrophilic side chain?
A. Asn B. Leu C. Ile D. Gly
15. Which of the following amino acids has a side chain that can make hydrogen bonds to other
molecules? A. Leu
B. Ser
C. Ala
, D. Gly
16. Asp and Glu both have amides as side chains. A. True
B. False
17. Thr and Ser both have hydroxyls as side chains. A. True
B. False
18. The side chain of Met is a poor hydrogen bond donor. A. True
B. False
19. Which group consists only of amino acids with carboxylate side chains? A. glutamate and
cysteine
B. aspartate and glycine
C. glutamate and lysine
D. aspartate and glutamate
20. Which group consists only of amino acids with basic side chains? A. leucine and lysine
B. arginine and leucine
C. lysine and arginine
D. arginine and isoleucine
21. Which amino acids contain sulfur? A. cysteine and lysine
B. cysteine and methionine
C. arginine and methionine
D. cysteine and isoleucine
22. Which amino acid takes on a negative charge when the R-group loses a proton? A. Glutamic
Acid
B. Histidine
C. Glutamine
D. Tyrosine
E. Glutamic Acid and Tyrosine
23. Which amino acid takes on a positive charge when the R-group gains a proton? A. Glutamic
Acid
B. Histidine
C. Glutamine
D. Tyrosine E. Glycine