BBL MIDTERM QUESTIONS AND
VERIFIED ANSWERS|100%
CORRECT|GRADE A+
All amino acids are formed by the amination of
A. Sugars
B. Keto acids
C. Short-chain fatty acids
D. Esters - ANSWER B
The major metabolic source of amino acid precursors is
A. Glycolysis
B. Gluconeogensis
C. TCA Cycle
D. Pentose phosphate pathway - ANSWER C
Which amino acid is formed on a t-RNA?
A. Tryptophan
B. Selenocysteine
C. Methionine
D. Alanine - ANSWER B
All amino acids have an R group. What is the significance of the R?
A. Each of the 21 amino acids has a unique R group
B. Proline and glycine are the only amino acids without an R group
C. All R groups have charge
D. Not all R groups are bound to the alpha carbon - ANSWER A
At neutral pH, all amino acids are
,A. Zwitterionic, with both the amine and carboxylic acids charged
B. Protonated at the amine group
C. Uncharged, and non-reactive
D. Deprotonated at the carboxylic acid - ANSWER A
Of the following amino acids, whose R group has charge?
A. Leucine, valine, tryptophan
B. Arginine, glycine, isoleucine
C. Methionine, cysteine, alanine
D. Arginine, lysine, glutamate - ANSWER D
Which of the following amino acids does not have chirality?
A. Alanine
B. Cysteine
C. Glycine
D. Proline - ANSWER C
Which are branched chain amino acids?
A. Methionine, cysteine, alanine
B. Tyrosine, tryptophan, phenylalanine
C. Serine, glycine, threonine
D. Isoleucine, leucine, valine - ANSWER D
Which amino acids' R groups are basic?
A. Aspartate and glutamate
B. Lysine, arginine and histidine
C. Isoleucine, leucine and valine
D. Cysteine, methionine and selenocysteine - ANSWER B
,Which amino acids have aromatic R groups?
A. Phenylalanine, tryptophan and tyrosine
B. Arginine, histidine and lysine
C. Alanine, glycine and proline
D. Serine, threonine and tyrosine - ANSWER A
The major use of methionine is in
A. Protein synthesis
B. Forming cysteine through the transulfuration pathway so it is a non-essential amino acid
C. Adenylylation of methionine by ATP to form S'adenosylmethionine
D. Formation of polyamines - ANSWER C
The unique amino acid found in the elastin protein is
A. Ornithine
B. S'Adenosylmethionine
C. Desmosine
D. Carboxyglutamic acid - ANSWER C
What statement best describes the pathway that forms Selenocysteine?
A. A swap of selenide for sulfur in the R group of cysteine
B. Selenide adds the seleno group to a seryl-tRNA, forming selnocystyl-tRNA, that is then added to
growing peptide chain
C. Seleno group is added to cystyl residue as post-transcriptional modification
D. A protein seryl group residue in a protein has a seleno group added as a post transcriptional
modification to form selenocystyl residue - ANSWER B
The uncommon amino acid ornithine
A. Is found at the first amino acid at the N terminal of a protein
B. Causes loss of beta sheet in protein
, C. Is the starting substrate of the Urea Cycle
D. Exclusively found in alpha helix proteins - ANSWER C
The isoelectric point (pI) of a non-polar amino acid is the pH where
A. It has maximum charge
B. It is strongly acidic
C. It is strongly basic
D. Both amine and carboxylic acids are charged and the amino acid has zero net charge - ANSWER D
Alanine has a pK1 and a pK2 while lysine has a pK1, pK2 and a pKR. Why?
A. The R group of alanine is acidic
B. The R group of lysine is neutral
C. The R group of alanine is non-polar while lysine has a charged R group
D. Both alanine and lysine have neutral R groups - ANSWER C
What amino acids have pKR in the acid range?
A. Isoleucine and leucine
B. Glutamate and aspartate
C. Arginine and lysine
D. Asparagine and glutamine - ANSWER B
Of the amino acids in protein, how many do not ionize?
A. 10
B. All
C. None
D. 13 - ANSWER D
Where are the polar amino acids found in protein?
A. In the interior of globular protein structure
VERIFIED ANSWERS|100%
CORRECT|GRADE A+
All amino acids are formed by the amination of
A. Sugars
B. Keto acids
C. Short-chain fatty acids
D. Esters - ANSWER B
The major metabolic source of amino acid precursors is
A. Glycolysis
B. Gluconeogensis
C. TCA Cycle
D. Pentose phosphate pathway - ANSWER C
Which amino acid is formed on a t-RNA?
A. Tryptophan
B. Selenocysteine
C. Methionine
D. Alanine - ANSWER B
All amino acids have an R group. What is the significance of the R?
A. Each of the 21 amino acids has a unique R group
B. Proline and glycine are the only amino acids without an R group
C. All R groups have charge
D. Not all R groups are bound to the alpha carbon - ANSWER A
At neutral pH, all amino acids are
,A. Zwitterionic, with both the amine and carboxylic acids charged
B. Protonated at the amine group
C. Uncharged, and non-reactive
D. Deprotonated at the carboxylic acid - ANSWER A
Of the following amino acids, whose R group has charge?
A. Leucine, valine, tryptophan
B. Arginine, glycine, isoleucine
C. Methionine, cysteine, alanine
D. Arginine, lysine, glutamate - ANSWER D
Which of the following amino acids does not have chirality?
A. Alanine
B. Cysteine
C. Glycine
D. Proline - ANSWER C
Which are branched chain amino acids?
A. Methionine, cysteine, alanine
B. Tyrosine, tryptophan, phenylalanine
C. Serine, glycine, threonine
D. Isoleucine, leucine, valine - ANSWER D
Which amino acids' R groups are basic?
A. Aspartate and glutamate
B. Lysine, arginine and histidine
C. Isoleucine, leucine and valine
D. Cysteine, methionine and selenocysteine - ANSWER B
,Which amino acids have aromatic R groups?
A. Phenylalanine, tryptophan and tyrosine
B. Arginine, histidine and lysine
C. Alanine, glycine and proline
D. Serine, threonine and tyrosine - ANSWER A
The major use of methionine is in
A. Protein synthesis
B. Forming cysteine through the transulfuration pathway so it is a non-essential amino acid
C. Adenylylation of methionine by ATP to form S'adenosylmethionine
D. Formation of polyamines - ANSWER C
The unique amino acid found in the elastin protein is
A. Ornithine
B. S'Adenosylmethionine
C. Desmosine
D. Carboxyglutamic acid - ANSWER C
What statement best describes the pathway that forms Selenocysteine?
A. A swap of selenide for sulfur in the R group of cysteine
B. Selenide adds the seleno group to a seryl-tRNA, forming selnocystyl-tRNA, that is then added to
growing peptide chain
C. Seleno group is added to cystyl residue as post-transcriptional modification
D. A protein seryl group residue in a protein has a seleno group added as a post transcriptional
modification to form selenocystyl residue - ANSWER B
The uncommon amino acid ornithine
A. Is found at the first amino acid at the N terminal of a protein
B. Causes loss of beta sheet in protein
, C. Is the starting substrate of the Urea Cycle
D. Exclusively found in alpha helix proteins - ANSWER C
The isoelectric point (pI) of a non-polar amino acid is the pH where
A. It has maximum charge
B. It is strongly acidic
C. It is strongly basic
D. Both amine and carboxylic acids are charged and the amino acid has zero net charge - ANSWER D
Alanine has a pK1 and a pK2 while lysine has a pK1, pK2 and a pKR. Why?
A. The R group of alanine is acidic
B. The R group of lysine is neutral
C. The R group of alanine is non-polar while lysine has a charged R group
D. Both alanine and lysine have neutral R groups - ANSWER C
What amino acids have pKR in the acid range?
A. Isoleucine and leucine
B. Glutamate and aspartate
C. Arginine and lysine
D. Asparagine and glutamine - ANSWER B
Of the amino acids in protein, how many do not ionize?
A. 10
B. All
C. None
D. 13 - ANSWER D
Where are the polar amino acids found in protein?
A. In the interior of globular protein structure
