Question 1

Which one of the following naturally occurring amino acids does not have an S configuration?

Accepted Answer

A)  Cysteine
B)  Alanine
C)  Tyrosine
D)  IsoleucineE) C) and D)
F) B) and C)

Question 2

What is the product of the following reaction? (Assume workup to neutralize.)

Accepted Answer

A)  I
B)  II
C)  III
D)  IVE) All of the above
F) B) and C)

Question 3

Amino acid synthesis is possible by all except one of the pathways listed.Which is not a synthetic pathway for amino acids?

Accepted Answer

A)  Amination of malonic ester followed by hydrolysis and decarboxylation
B)  Nucleophilic addition of NH3 to an aldehyde followed by addition of cyanide to the imine,and,finally,hydrolysis
C)  SN2 reaction using an a-halo carboxylic acid with ammonia as the nucleophile
D)  Reaction of NH4Cl and NaCN with an aldehyde followed by an acidic work-upE) C) and D)
F) None of the above

Question 4

Below is a proposed method for resolving a racemic mixture of (R) - and (S) -phenylalanine.Upon separation of the products,will this method produce (R) - or (S) -phenylalanine?

Accepted Answer

A)  (R) -Phenylalanine is produced since the acylase only hydrolyzes the amides of L-amino acids.
B)  (S) -Phenylalanine is produced since the acylase only hydrolyzes the amides of L-amino acids.
C)  (R) -Phenylalanine is produced since the acylase only hydrolyzes the amides of D-amino acids.
D)  (S) -Phenylalanine is produced since the acylase only hydrolyzes the amides of D-amino acids.E) C) and D)
F) A) and C)

Question 5

What amino acid is at the N-terminus of the following peptide?

Accepted Answer

A)  Valine
B)  Serine
C)  Alanine
D)  ProlineE) B) and C)
F) A) and C)

Question 6

Which of the following is the correct structure for alanine at pH = 7?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) A) and D)
F) B) and D)

Question 7

Why does the formation of salts of a racemic mixture of N-acetyl valine with a single enantiomer of a-methylbenzylamine enable the separation of the two enantiomers of N-acetyl valine?

Accepted Answer

A)  They form amides.
B)  They form diastereomers.
C)  They form salts.
D)  They form meso compounds.E) C) and D)
F) None of the above

Question 8

Which is the correct structure for the amino acid proline?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) A) and D)
F) C) and D)

Question 9

What are the basic steps in the Merrifield peptide synthesis?

Accepted Answer

A)  Coupling and hydrolysis
B)  Hydrolysis and deprotection
C)  Deprotection and hydrogenation
D)  Coupling and deprotectionE) A) and C)
F) A) and B)

Question 10

Which is the correct structure for serine?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) B) and D)
F) A) and D)

Question 11

Which of the following amino acids does not have an L-isomer?

Accepted Answer

A)  Alanine
B)  Valine
C)  Glycine
D)  LeucineE) A) and B)
F) None of the above

Question 12

What is the major organic product for the following reaction?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) A) and D)
F) A) and B)

Question 13

Which is the correct structure for the amino acid valine?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) B) and C)
F) A) and B) C

Question 14

Which of the following correctly describes a protein?

Accepted Answer

A)  a dipeptide; two amino acids joined together by one amide bond
B)  a tripeptide; three amino acids joined together by two amide bonds
C)  a polymer of more than 40 amino acids joined together by amide bonds
D)  a polypeptide of any number of amino acids joined together by amide bondsE) C) and D)
F) A) and D)

Question 15

Which of the following is (are) globular protein(s) ?

Accepted Answer

A)  Hemoglobin
B)  Keratins
C)  Collagens
D)  ElastinsE) All of the above
F) B) and D) A

Question 16

Which of the following aldehydes would be a good starting material in the Strecker synthesis of phenylalanine?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) B) and C)
F) All of the above

Question 17

Below is a 2D chromatogram that shows the separation of five amino acids.In this technique,the amino acid mixture is first separated by chromatography using a polar solvent system.Then the plate is rotated 90°,and the amino acids are further separated by electrophoresis.Identify the spots obtained from a mixture of Trp,Glu,Lys,Ile and Thr.A table with isoelectric points is included to aid in solving this problem.  amino acid-pI value Trp-5.9
Glu-3.2
Lys-9.7
Ile-6.0
Thr-5.6

Accepted Answer

A)  1=Lys,2=Thr,3=Glu,4=Trp,5=Ile
B)  1=Glu,2=Thr,3=Lys,4=Trp,5=Ile
C)  1=Lys,2=Ile,3=Glu,4=Trp,5=Thr
D)  1=Glu,2=Ile,3=Lys,4=Trp,5=ThrE) None of the above
F) A) and B)

Question 18

What is the appropriate sequence of reaction conditions used to synthesize valine from acetamidomalonic ester? 3) 2CHBr; (3) Cl2,H2O,heat B) (1) NaOCH2CH3; (2) (CH3) 2CH2CHBr; (3) HCl,H2O,heat C) (1) NaOCH2CH3; (2) (CH3) 2CHBr; (3) HCl,H2O,heat D) (1) NaOH; (2) CH3CH2CH2Br; (3) HCl,H2O,heat" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  (1) NaOH; (2) (CH3) 2CHBr; (3) Cl2,H2O,heat
B)  (1) NaOCH2CH3; (2) (CH3) 2CH2CHBr; (3) HCl,H2O,heat
C)  (1) NaOCH2CH3; (2) (CH3) 2CHBr; (3) HCl,H2O,heat
D)  (1) NaOH; (2) CH3CH2CH2Br; (3) HCl,H2O,heatE) B) and C)
F) A) and D)

Question 19

What reagents would you use to convert acetaldehyde into alanine?

Accepted Answer

A)  NH3
B)  HCN
C)  NaCN,NH4Cl
D)  NaNH2E) All of the above
F) B) and C)

Question 20

Which of the following is the structure of the amino acid lysine?

Accepted Answer

A)  A
B)  B
C)  C
D)  DE) B) and C)
F) A) and D) A

Exam 27: Amino Acids and Proteins

Which one of the following naturally occurring amino acids does not have an S configuration?

Correct Answer
verified

What is the product of the following reaction? (Assume workup to neutralize.)

Correct Answer
verified

Amino acid synthesis is possible by all except one of the pathways listed.Which is not a synthetic pathway for amino acids?

Correct Answer
verified

Below is a proposed method for resolving a racemic mixture of (R) - and (S) -phenylalanine.Upon separation of the products,will this method produce (R) - or (S) -phenylalanine?

Correct Answer
verified

What amino acid is at the N-terminus of the following peptide?

Correct Answer
verified

Which of the following is the correct structure for alanine at pH = 7?

Correct Answer
verified

Why does the formation of salts of a racemic mixture of N-acetyl valine with a single enantiomer of a-methylbenzylamine enable the separation of the two enantiomers of N-acetyl valine?

Correct Answer
verified

Which is the correct structure for the amino acid proline?

Correct Answer
verified

What are the basic steps in the Merrifield peptide synthesis?

Correct Answer
verified

Which is the correct structure for serine?

Correct Answer
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Which of the following amino acids does not have an L-isomer?

Correct Answer
verified

What is the major organic product for the following reaction?

Correct Answer
verified

Which is the correct structure for the amino acid valine?

Correct Answer
verified
C

Which of the following correctly describes a protein?

Correct Answer
verified

Which of the following is (are) globular protein(s) ?

Correct Answer
verified
A

Which of the following aldehydes would be a good starting material in the Strecker synthesis of phenylalanine?

Correct Answer
verified

Correct Answer
verified

What is the appropriate sequence of reaction conditions used to synthesize valine from acetamidomalonic ester?

Correct Answer
verified

What reagents would you use to convert acetaldehyde into alanine?

Correct Answer
verified

Which of the following is the structure of the amino acid lysine?

Correct Answer
verified
A

Exam 27: Amino Acids and Proteins

Which one of the following naturally occurring amino acids does not have an S configuration?

Correct AnswerverifiedShow Answer

What is the product of the following reaction? (Assume workup to neutralize.)

Correct AnswerverifiedShow Answer

Amino acid synthesis is possible by all except one of the pathways listed.Which is not a synthetic pathway for amino acids?

Correct AnswerverifiedShow Answer

Below is a proposed method for resolving a racemic mixture of (R) - and (S) -phenylalanine.Upon separation of the products,will this method produce (R) - or (S) -phenylalanine?

Correct AnswerverifiedShow Answer

What amino acid is at the N-terminus of the following peptide?

Correct AnswerverifiedShow Answer

Which of the following is the correct structure for alanine at pH = 7?

Correct AnswerverifiedShow Answer

Why does the formation of salts of a racemic mixture of N-acetyl valine with a single enantiomer of a-methylbenzylamine enable the separation of the two enantiomers of N-acetyl valine?

Correct AnswerverifiedShow Answer

Which is the correct structure for the amino acid proline?

Correct AnswerverifiedShow Answer

What are the basic steps in the Merrifield peptide synthesis?

Correct AnswerverifiedShow Answer

Which is the correct structure for serine?

Correct AnswerverifiedShow Answer

Which of the following amino acids does not have an L-isomer?

Correct AnswerverifiedShow Answer

What is the major organic product for the following reaction?

Correct AnswerverifiedShow Answer

Which is the correct structure for the amino acid valine?

Correct AnswerverifiedC

Which of the following correctly describes a protein?

Correct AnswerverifiedShow Answer

Which of the following is (are) globular protein(s) ?

Correct AnswerverifiedA

Which of the following aldehydes would be a good starting material in the Strecker synthesis of phenylalanine?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

What is the appropriate sequence of reaction conditions used to synthesize valine from acetamidomalonic ester?

Correct AnswerverifiedShow Answer

What reagents would you use to convert acetaldehyde into alanine?

Correct AnswerverifiedShow Answer

Which of the following is the structure of the amino acid lysine?

Correct AnswerverifiedA

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C

Correct Answer
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A

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A