WGU Biochemistry 2025/2026 Exam
Questions and Verified Answers |
Already Graded A+
DNA replication is ___________, which allows each of the two strands to
serve as a _______ for the new strands.
b. semiconservative, template - 🧠 ANSWER ✔✔DNA replication is
semiconservative, meaning that each new duplex has one original (parent)
strand and one new strand. Because the two parent strands are separated
during replication and the base pairing is predictable, each parent strand
can serve as a template for the new strand synthesis.
Which of the following enzymes does NOT assist the DNA polymerase on
the lagging strand to overcome its two problems? (Recall that the DNA
polymerase can only make DNA in the 5'->3' direction, and it must bind a
,double-stranded nucleotide polymer before it can start making its own DNA
polymer.)
c. Helicase - 🧠 ANSWER ✔✔Helicase unwinds the double stranded DNA to
allow for replication, but this is not a problem for the DNA polymerase.
Several components of cigarette smoke, including benzopyrene, insert
themselves (intercalate) into the DNA and lead to several types of
mutations such as frameshift mutations, including both insertions and
deletion. Which of the following repair pathways would be used to repair
this type of damage?
c. Nucleotide Excision Repair - 🧠 ANSWER ✔✔Nucleotide excision repair
is used to repair deletions, insertions, and helix-distorting lesions, such as
thymine dimers.
Maternal smoking during pregnancy is hazardous yet common in many
places. Many studies have associated prenatal smoking to unhealthy
physical and psychological outcomes for the baby. Researchers know that
,maternal smoking affects are epigenetic in nature. Which of the following
events can be considered epigenetic in nature?
a. Changes in chromatin structure - 🧠 ANSWER ✔✔Frame shift mutations
are a kind of mutations which result from addition of deletion of a nucleotide
base resulting in an altered reading frame and ultimately a different protein,
than the one the gene originally encoded. Frameshift mutations are genetic
changes because they alter the DNA sequence, whereas epigenetic
changes do not alter the DNA sequence. Epigenetic changes are
modifications to genomic structure (not sequence) that are caused by the
external environment. These environmental factors affect the overall
chromatin structure to allow more or less "access" to the DNA by gene
expression machinery to turn the genes "on" or "off". In other words,
epigenetics can alter gene expression without changing the underlying
DNA sequences. The changes may or may not be heritable, depending on
the location and circumstances.
Blood type is an example of what type of inheritance?
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STATEMENT. ALL RIGHTS RESERVED
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, a. Codominance - 🧠 ANSWER ✔✔The genes that produce the A and B
antigen proteins can both be expressed independently, and a heterozygote
(someone with both genes) will be produce both A and B proteins - neither
will dominate the other. The is an example of codominance.
What is the expected probability that a child will have an autosomal
dominant disease if their father is heterozygous for the allele and their
mother is homozygous for the normal allele?
a. 50% - 🧠 ANSWER ✔✔If D is the disease-conferring dominant allele and
d is the normal allele, the father has the genotype Dd and the mother's
genotype is dd. Each child can only inherit a d allele from their mother, and
they have a 50% chance of inheriting the D allele from their father. As a
result, the expected probability that their child will inherit the disease is
50%.
The physical trait of lip protrusion exhibits a characteristic type of
inheritance, as shown by the pedigree above. What type of inheritance best
describes this inheritance pattern?
Questions and Verified Answers |
Already Graded A+
DNA replication is ___________, which allows each of the two strands to
serve as a _______ for the new strands.
b. semiconservative, template - 🧠 ANSWER ✔✔DNA replication is
semiconservative, meaning that each new duplex has one original (parent)
strand and one new strand. Because the two parent strands are separated
during replication and the base pairing is predictable, each parent strand
can serve as a template for the new strand synthesis.
Which of the following enzymes does NOT assist the DNA polymerase on
the lagging strand to overcome its two problems? (Recall that the DNA
polymerase can only make DNA in the 5'->3' direction, and it must bind a
,double-stranded nucleotide polymer before it can start making its own DNA
polymer.)
c. Helicase - 🧠 ANSWER ✔✔Helicase unwinds the double stranded DNA to
allow for replication, but this is not a problem for the DNA polymerase.
Several components of cigarette smoke, including benzopyrene, insert
themselves (intercalate) into the DNA and lead to several types of
mutations such as frameshift mutations, including both insertions and
deletion. Which of the following repair pathways would be used to repair
this type of damage?
c. Nucleotide Excision Repair - 🧠 ANSWER ✔✔Nucleotide excision repair
is used to repair deletions, insertions, and helix-distorting lesions, such as
thymine dimers.
Maternal smoking during pregnancy is hazardous yet common in many
places. Many studies have associated prenatal smoking to unhealthy
physical and psychological outcomes for the baby. Researchers know that
,maternal smoking affects are epigenetic in nature. Which of the following
events can be considered epigenetic in nature?
a. Changes in chromatin structure - 🧠 ANSWER ✔✔Frame shift mutations
are a kind of mutations which result from addition of deletion of a nucleotide
base resulting in an altered reading frame and ultimately a different protein,
than the one the gene originally encoded. Frameshift mutations are genetic
changes because they alter the DNA sequence, whereas epigenetic
changes do not alter the DNA sequence. Epigenetic changes are
modifications to genomic structure (not sequence) that are caused by the
external environment. These environmental factors affect the overall
chromatin structure to allow more or less "access" to the DNA by gene
expression machinery to turn the genes "on" or "off". In other words,
epigenetics can alter gene expression without changing the underlying
DNA sequences. The changes may or may not be heritable, depending on
the location and circumstances.
Blood type is an example of what type of inheritance?
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
3
, a. Codominance - 🧠 ANSWER ✔✔The genes that produce the A and B
antigen proteins can both be expressed independently, and a heterozygote
(someone with both genes) will be produce both A and B proteins - neither
will dominate the other. The is an example of codominance.
What is the expected probability that a child will have an autosomal
dominant disease if their father is heterozygous for the allele and their
mother is homozygous for the normal allele?
a. 50% - 🧠 ANSWER ✔✔If D is the disease-conferring dominant allele and
d is the normal allele, the father has the genotype Dd and the mother's
genotype is dd. Each child can only inherit a d allele from their mother, and
they have a 50% chance of inheriting the D allele from their father. As a
result, the expected probability that their child will inherit the disease is
50%.
The physical trait of lip protrusion exhibits a characteristic type of
inheritance, as shown by the pedigree above. What type of inheritance best
describes this inheritance pattern?
