C785 Biochemistry preassessment Exam
2026 Questions and Answers
Assuming 100% reaction efficiency, how many DNA copies are created after the
completion of four complete PCR cycles? - Correct answer-16
What is the function of DNA polymerase in the process of PCR? - Correct answer-
It recognizes the primers and uses the available dNTPs to replicate the template
DNA sequence.
What are possible blood types of the parents of a patient with blood type AB? -
Correct answer-A and B
115 116 117 118 − Amino Acid Number
Tyr Gly Thr Pro − Amino Acid Sequence
TAC GGG ACA CCA − DNA Sequence
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, What is the amino acid in position 118 that results from a single nucleotide
insertion immediately following the three guanines that encode for glycine 116? -
Correct answer-Thr
In sickle-cell disease, the glutamic acid (Glu) at position number seven is mutated
to valine (Val).
What change in codons corresponds to this mutation? - Correct answer-GAA to
GTA
Which type of mammalian DNA damage repair requires the presence of the
chromosome that is homologous to the damaged chromosome? - Correct answer-
Recombination
Xeroderma pigmentosum (XP) is a recessive genetic disease that occurs when one
or more of the genes that perform nucleotide excision repair are nonfunctional.
Why do XP patients have a much higher incidence of skin cancer than the general
population? - Correct answer-The mutation rate of all other genes is higher due to
failure to repair.
©COPYRIGHT 2025, ALL RIGHTS RESERVE 2
2026 Questions and Answers
Assuming 100% reaction efficiency, how many DNA copies are created after the
completion of four complete PCR cycles? - Correct answer-16
What is the function of DNA polymerase in the process of PCR? - Correct answer-
It recognizes the primers and uses the available dNTPs to replicate the template
DNA sequence.
What are possible blood types of the parents of a patient with blood type AB? -
Correct answer-A and B
115 116 117 118 − Amino Acid Number
Tyr Gly Thr Pro − Amino Acid Sequence
TAC GGG ACA CCA − DNA Sequence
©COPYRIGHT 2025, ALL RIGHTS RESERVE 1
, What is the amino acid in position 118 that results from a single nucleotide
insertion immediately following the three guanines that encode for glycine 116? -
Correct answer-Thr
In sickle-cell disease, the glutamic acid (Glu) at position number seven is mutated
to valine (Val).
What change in codons corresponds to this mutation? - Correct answer-GAA to
GTA
Which type of mammalian DNA damage repair requires the presence of the
chromosome that is homologous to the damaged chromosome? - Correct answer-
Recombination
Xeroderma pigmentosum (XP) is a recessive genetic disease that occurs when one
or more of the genes that perform nucleotide excision repair are nonfunctional.
Why do XP patients have a much higher incidence of skin cancer than the general
population? - Correct answer-The mutation rate of all other genes is higher due to
failure to repair.
©COPYRIGHT 2025, ALL RIGHTS RESERVE 2
