Advanced Biochemistry Final Exam
Questions and Answers 100% Pass
What is the limiting substance in the biosynthesis of purines?
A. ribose-5-phosphate
B. 5-phosphoribosyl-β amine
C. formylglycinamidine ribonucleotide
D. 5-phosphoribosyl-α-pyrophosphate (PRPP)
E. α-D-ribose-5-phosphate - ✔✔D
The coenzyme for two single carbon additions in purine biosynthesis is:
A. THF
B. biotin
C. SAM
D. TPP
E. none are true - ✔✔A
What is the common product of purine catabolism?
A. xanthine
B. uric acid
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,C. inosine
D. hypoxanthine
E. xanthosine - ✔✔B
Thymidylate synthase synthesizes dTMP from __ by __ , utilizing the
coenzyme __.
A. dCTP; carboxylation; biotin
B. dUMP; methylation; THF
C. dCMP; methylation; THF
D. dGMP; phosphorylation; ATP
E. dUMP; phosphorylation; ATP - ✔✔B
Which is a six-membered heterocyclic aromatic ring?
A. pyrimidine
B. purine
C. anose
D. sugar portion of DNA
E. ribonucleotide - ✔✔A
Which of the following statements regarding the structure of DNA is
correct?
A. the two strands are parallel
B. the two strands are held together by intrachain hydrogen bonds
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,C. the two strands have complementary base pairing
D. the ;hydrogen bonding that holds the helix together is always between
two purines or between two pyrimidines
E. the ratio of adenine to guanine is the same in all organisms - ✔✔C
The convention in all notations of nucleic acid structure is to read the
polynucleotide chain from the __ of the polymer to the __.
A. poly U head; poly A tail
B. 3' end; 5' tail
C. 5' end; 3' end
D. poly-p head; 5' head
E. none are true - ✔✔C
In eukaryotic cells, a class of __- and __-rich proteins called __ interact
ionically with the anionic phosphate groups in the DNA backbone to form
__.
A. lysine; leucine; prions; ribosomes
B. arginine; lysine; histones; nucleosomes
C. arginine; alanine; histones; nucleosomes
D. arginine; lysine; prions; ribosomes
E. none are true - ✔✔B
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, Eukaryotic mRNAs are synthesized in the nucleus, are called __, and
contain noncoding regions called __ because they intervene between
coding regions called __.
A. poly A RNAs; noncodons; codons
B. poly A RNAs; intervening sequences; codons
C. heterogeneous nuclear RNAs; intervening sequences (introns); codons
D. heterogeneous nuclear RNAs; intervening sequenes (introns); exons
E. none of the above - ✔✔D
Enzymes that catalyze the unwinding of DNA double helices are:
A. topoisomerases
B. helicases
C. ligases
D. gyrases
E. polymerases - ✔✔B
SSBs are:
A. substrates for DNA ligases
B. supercoil stabilizing bodies
C. single-stranded bodies called Okazaki fragments
D. single-stranded DNA binding proteins that prevent re-annealing
E. nucleases that hydrolyze single-stranded RNA primers - ✔✔D
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Questions and Answers 100% Pass
What is the limiting substance in the biosynthesis of purines?
A. ribose-5-phosphate
B. 5-phosphoribosyl-β amine
C. formylglycinamidine ribonucleotide
D. 5-phosphoribosyl-α-pyrophosphate (PRPP)
E. α-D-ribose-5-phosphate - ✔✔D
The coenzyme for two single carbon additions in purine biosynthesis is:
A. THF
B. biotin
C. SAM
D. TPP
E. none are true - ✔✔A
What is the common product of purine catabolism?
A. xanthine
B. uric acid
1
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
,C. inosine
D. hypoxanthine
E. xanthosine - ✔✔B
Thymidylate synthase synthesizes dTMP from __ by __ , utilizing the
coenzyme __.
A. dCTP; carboxylation; biotin
B. dUMP; methylation; THF
C. dCMP; methylation; THF
D. dGMP; phosphorylation; ATP
E. dUMP; phosphorylation; ATP - ✔✔B
Which is a six-membered heterocyclic aromatic ring?
A. pyrimidine
B. purine
C. anose
D. sugar portion of DNA
E. ribonucleotide - ✔✔A
Which of the following statements regarding the structure of DNA is
correct?
A. the two strands are parallel
B. the two strands are held together by intrachain hydrogen bonds
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©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
,C. the two strands have complementary base pairing
D. the ;hydrogen bonding that holds the helix together is always between
two purines or between two pyrimidines
E. the ratio of adenine to guanine is the same in all organisms - ✔✔C
The convention in all notations of nucleic acid structure is to read the
polynucleotide chain from the __ of the polymer to the __.
A. poly U head; poly A tail
B. 3' end; 5' tail
C. 5' end; 3' end
D. poly-p head; 5' head
E. none are true - ✔✔C
In eukaryotic cells, a class of __- and __-rich proteins called __ interact
ionically with the anionic phosphate groups in the DNA backbone to form
__.
A. lysine; leucine; prions; ribosomes
B. arginine; lysine; histones; nucleosomes
C. arginine; alanine; histones; nucleosomes
D. arginine; lysine; prions; ribosomes
E. none are true - ✔✔B
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©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
, Eukaryotic mRNAs are synthesized in the nucleus, are called __, and
contain noncoding regions called __ because they intervene between
coding regions called __.
A. poly A RNAs; noncodons; codons
B. poly A RNAs; intervening sequences; codons
C. heterogeneous nuclear RNAs; intervening sequences (introns); codons
D. heterogeneous nuclear RNAs; intervening sequenes (introns); exons
E. none of the above - ✔✔D
Enzymes that catalyze the unwinding of DNA double helices are:
A. topoisomerases
B. helicases
C. ligases
D. gyrases
E. polymerases - ✔✔B
SSBs are:
A. substrates for DNA ligases
B. supercoil stabilizing bodies
C. single-stranded bodies called Okazaki fragments
D. single-stranded DNA binding proteins that prevent re-annealing
E. nucleases that hydrolyze single-stranded RNA primers - ✔✔D
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©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
