| Adv Pathophysiology (2026) Q&A
1. Which statement accurately describes the structural relationship between genes,
chromosomes, and DNA?
A) Genes are messenger RNA (mRNA) molecules that carry genetic information.
B) Genes are cells that determine gender during fertilization.
C) Genes are structures within chromosomes of each cell that contain
deoxyribonucleic acid (DNA).
D) Genes are antibodies that promote disease through immune mechanisms.
Correct Answer: Genes are structures within chromosomes of each cell that
contain deoxyribonucleic acid (DNA).
Rationale: Genes are segments of DNA located within chromosomes and serve as
the fundamental units of heredity, containing instructions for protein synthesis.
They are not mRNA molecules, cells, or antibodies. This structural relationship is
foundational to understanding genetics and gene expression.
2. What is the primary function of histones within a eukaryotic cell?
A) They serve as the primary site of ATP synthesis.
B) They facilitate the supercoiling and organization of DNA into chromosomes.
C) They act as channels for the transport of ions across the plasma membrane.
D) They catalyze the breakdown of cellular waste products.
Correct Answer: They facilitate the supercoiling and organization of DNA into
chromosomes.
,Rationale: Histones are binding proteins that cause the supercoiling of DNA into
compact chromosomes, playing a crucial role in DNA packaging and regulation.
They are not involved in ATP synthesis, ion transport, or waste breakdown, which
are functions of other cellular components.
3. Which enzyme is responsible for synthesizing a new DNA strand by adding
complementary nucleotides during replication?
A) RNA polymerase
B) Helicase
C) DNA polymerase
D) Ligase
Correct Answer: DNA polymerase
Rationale: DNA polymerase is the enzyme responsible for synthesizing new DNA
strands by adding complementary nucleotides to the growing strand during
replication. RNA polymerase synthesizes RNA, helicase unwinds the double helix,
and ligase joins DNA fragments.
4. What is the process by which RNA is synthesized from a DNA template?
A) Replication
B) Transcription
C) Translation
D) Reverse transcription
Correct Answer: Transcription
, Rationale: Transcription is the process by which RNA is synthesized from a DNA
template, allowing genetic information to be transferred from the nucleus to the
cytoplasm. Replication copies DNA, translation synthesizes proteins from mRNA,
and reverse transcription synthesizes DNA from RNA.
5. Which type of genetic inheritance is characterized by an affected parent
transmitting the trait to 50% of offspring, with both sexes equally affected?
A) Autosomal recessive
B) X-linked recessive
C) Autosomal dominant
D) Mitochondrial
Correct Answer: Autosomal dominant
Rationale: Autosomal dominant inheritance occurs when a single copy of a
mutant allele is sufficient to express the phenotype, leading to a 50% chance of
transmission from a heterozygous affected parent to offspring of either sex.
Autosomal recessive requires two copies, X-linked recessive primarily affects
males, and mitochondrial inheritance is maternal.
6. In autosomal recessive inheritance, what is the probability that two carrier
parents will have an affected child?
A) 0%
B) 25%
C) 50%
D) 100%