NR507 ADVANCED PATHOPHYSIOLOGY MIDTERM EXAM
300 QUESTIONS AND ANSWERS WITH RATIONALE
LATEST UPDATE THIS YEAR JUST RELEASED!!!!!!!!!!!!!!
Section 1: Cellular Biology and Genetics
1. A patient with a genetic disorder exhibits symptoms due to the activation of a
mutant gene that was previously inactive. This phenomenon is best described
as:
A. Pleiotropy
B. Penetrance
C. Expressivity
D. Anticipation
Answer: B. Penetrance
Rationale: Penetrance is the proportion of individuals with a specific genotype
who express the associated phenotype. If a mutant gene is present but inactive in
some, and active in others, it demonstrates incomplete penetrance. Pleiotropy is
one gene affecting multiple traits. Expressivity is the degree of phenotype
variation. Anticipation is earlier onset in subsequent generations.
2. Which cellular organelle is primarily responsible for the synthesis of lipids and
the detoxification of drugs?
A. Rough Endoplasmic Reticulum
B. Smooth Endoplasmic Reticulum
C. Golgi Apparatus
D. Lysosomes
Answer: B. Smooth Endoplasmic Reticulum
Rationale: The smooth ER lacks ribosomes and is involved in lipid synthesis,
carbohydrate metabolism, and detoxification of drugs and poisons. The rough ER
is for protein synthesis. The Golgi modifies and packages proteins. Lysosomes are
for intracellular digestion.
,3. A defect in which cellular structure would most directly impair the cell's
ability to generate ATP?
A. Peroxisome
B. Ribosome
C. Mitochondrion
D. Nucleus
Answer: C. Mitochondrion
Rationale: Mitochondria are the site of oxidative phosphorylation and the primary
generators of ATP (cellular energy). Peroxisomes break down fatty acids.
Ribosomes synthesize proteins. The nucleus houses genetic material.
4. A 5-year-old child is diagnosed with cystic fibrosis. This is an example of which
type of genetic inheritance?
A. Autosomal Dominant
B. Autosomal Recessive
C. X-linked Dominant
D. X-linked Recessive
Answer: B. Autosomal Recessive
Rationale: Cystic fibrosis is caused by mutations in the CFTR gene on chromosome
7 and requires two mutated copies (one from each parent) for the disease to
manifest. This is the classic pattern of autosomal recessive inheritance.
5. A cell is exposed to a toxin that inhibits the function of the Na+/K+ ATPase
pump. What is the most immediate consequence to the cell's resting membrane
potential?
A. Hyperpolarization
B. Depolarization
C. No change
D. Repolarization
Answer: B. Depolarization
Rationale: The Na+/K+ ATPase maintains the concentration gradients for sodium
and potassium. If inhibited, intracellular sodium increases and potassium
decreases, reducing the electrochemical gradient and making the cell more
positive (depolarized), thus making it more excitable.
,6. Which of the following is a characteristic of apoptosis, but NOT necrosis?
A. Inflammation of surrounding tissue
B. Cellular swelling
C. Chromatin condensation and fragmentation
D. Rupture of the plasma membrane
Answer: C. Chromatin condensation and fragmentation
Rationale: Apoptosis is programmed cell death characterized by cell shrinkage,
chromatin condensation, and DNA fragmentation without inflammation. Necrosis
is unprogrammed death featuring cell swelling, membrane rupture, and an
inflammatory response.
7. A patient has a mutation in a tumor suppressor gene. Which of the following
best describes the function of a normal tumor suppressor gene?
A. Promotes cell cycle progression
B. Inhibits cell growth and division
C. Repairs damaged DNA only
D. Activates proto-oncogenes
Answer: B. Inhibits cell growth and division
Rationale: Tumor suppressor genes normally act as "brakes" on cell growth,
preventing uncontrolled proliferation. When mutated (loss of function), this brake
is removed, allowing cancer to develop. Proto-oncogenes promote growth and
become oncogenes when mutated.
8. The cellular process of removing damaged organelles by enclosing them in a
membrane and fusing with a lysosome is called:
A. Phagocytosis
B. Pinocytosis
C. Autophagy
D. Exocytosis
Answer: C. Autophagy
Rationale: Autophagy is the process by which cells degrade their own damaged or
unnecessary components via a lysosome-dependent pathway. Phagocytosis is cell
"eating." Pinocytosis is cell "drinking." Exocytosis is exporting materials from the
cell.
, 9. A newborn has a genetic condition that leads to the accumulation of glycogen
in the liver and kidneys. Which organelle is most likely defective?
A. Nucleus
B. Mitochondria
C. Peroxisome
D. Lysosome
Answer: D. Lysosome
Rationale: Lysosomes contain enzymes for breaking down macromolecules.
Glycogen storage diseases like Pompe's disease are due to a deficiency of the
lysosomal enzyme acid alpha-glucosidase, leading to glycogen accumulation.
10. Which of the following RNA types carries the genetic code from DNA to the
ribosome for protein synthesis?
A. tRNA
B. rRNA
C. mRNA
D. snRNA
Answer: C. mRNA
Rationale: Messenger RNA (mRNA) carries the transcribed genetic code from the
nucleus to the ribosome in the cytoplasm, where it directs protein synthesis. tRNA
carries amino acids. rRNA makes up the ribosome. snRNA is involved in splicing.
11. A patient with a malignant tumor has a biopsy showing cells of varying sizes
and shapes. This feature is referred to as:
A. Hyperplasia
B. Metaplasia
C. Anaplasia
D. Hypertrophy
Answer: C. Anaplasia
Rationale: Anaplasia is a hallmark of malignant tumors characterized by loss of
cellular differentiation, pleomorphism (varying sizes and shapes), and atypical
nuclei. Hyperplasia is increased number of cells. Metaplasia is a change from one
mature cell type to another. Hypertrophy is an increase in cell size.
300 QUESTIONS AND ANSWERS WITH RATIONALE
LATEST UPDATE THIS YEAR JUST RELEASED!!!!!!!!!!!!!!
Section 1: Cellular Biology and Genetics
1. A patient with a genetic disorder exhibits symptoms due to the activation of a
mutant gene that was previously inactive. This phenomenon is best described
as:
A. Pleiotropy
B. Penetrance
C. Expressivity
D. Anticipation
Answer: B. Penetrance
Rationale: Penetrance is the proportion of individuals with a specific genotype
who express the associated phenotype. If a mutant gene is present but inactive in
some, and active in others, it demonstrates incomplete penetrance. Pleiotropy is
one gene affecting multiple traits. Expressivity is the degree of phenotype
variation. Anticipation is earlier onset in subsequent generations.
2. Which cellular organelle is primarily responsible for the synthesis of lipids and
the detoxification of drugs?
A. Rough Endoplasmic Reticulum
B. Smooth Endoplasmic Reticulum
C. Golgi Apparatus
D. Lysosomes
Answer: B. Smooth Endoplasmic Reticulum
Rationale: The smooth ER lacks ribosomes and is involved in lipid synthesis,
carbohydrate metabolism, and detoxification of drugs and poisons. The rough ER
is for protein synthesis. The Golgi modifies and packages proteins. Lysosomes are
for intracellular digestion.
,3. A defect in which cellular structure would most directly impair the cell's
ability to generate ATP?
A. Peroxisome
B. Ribosome
C. Mitochondrion
D. Nucleus
Answer: C. Mitochondrion
Rationale: Mitochondria are the site of oxidative phosphorylation and the primary
generators of ATP (cellular energy). Peroxisomes break down fatty acids.
Ribosomes synthesize proteins. The nucleus houses genetic material.
4. A 5-year-old child is diagnosed with cystic fibrosis. This is an example of which
type of genetic inheritance?
A. Autosomal Dominant
B. Autosomal Recessive
C. X-linked Dominant
D. X-linked Recessive
Answer: B. Autosomal Recessive
Rationale: Cystic fibrosis is caused by mutations in the CFTR gene on chromosome
7 and requires two mutated copies (one from each parent) for the disease to
manifest. This is the classic pattern of autosomal recessive inheritance.
5. A cell is exposed to a toxin that inhibits the function of the Na+/K+ ATPase
pump. What is the most immediate consequence to the cell's resting membrane
potential?
A. Hyperpolarization
B. Depolarization
C. No change
D. Repolarization
Answer: B. Depolarization
Rationale: The Na+/K+ ATPase maintains the concentration gradients for sodium
and potassium. If inhibited, intracellular sodium increases and potassium
decreases, reducing the electrochemical gradient and making the cell more
positive (depolarized), thus making it more excitable.
,6. Which of the following is a characteristic of apoptosis, but NOT necrosis?
A. Inflammation of surrounding tissue
B. Cellular swelling
C. Chromatin condensation and fragmentation
D. Rupture of the plasma membrane
Answer: C. Chromatin condensation and fragmentation
Rationale: Apoptosis is programmed cell death characterized by cell shrinkage,
chromatin condensation, and DNA fragmentation without inflammation. Necrosis
is unprogrammed death featuring cell swelling, membrane rupture, and an
inflammatory response.
7. A patient has a mutation in a tumor suppressor gene. Which of the following
best describes the function of a normal tumor suppressor gene?
A. Promotes cell cycle progression
B. Inhibits cell growth and division
C. Repairs damaged DNA only
D. Activates proto-oncogenes
Answer: B. Inhibits cell growth and division
Rationale: Tumor suppressor genes normally act as "brakes" on cell growth,
preventing uncontrolled proliferation. When mutated (loss of function), this brake
is removed, allowing cancer to develop. Proto-oncogenes promote growth and
become oncogenes when mutated.
8. The cellular process of removing damaged organelles by enclosing them in a
membrane and fusing with a lysosome is called:
A. Phagocytosis
B. Pinocytosis
C. Autophagy
D. Exocytosis
Answer: C. Autophagy
Rationale: Autophagy is the process by which cells degrade their own damaged or
unnecessary components via a lysosome-dependent pathway. Phagocytosis is cell
"eating." Pinocytosis is cell "drinking." Exocytosis is exporting materials from the
cell.
, 9. A newborn has a genetic condition that leads to the accumulation of glycogen
in the liver and kidneys. Which organelle is most likely defective?
A. Nucleus
B. Mitochondria
C. Peroxisome
D. Lysosome
Answer: D. Lysosome
Rationale: Lysosomes contain enzymes for breaking down macromolecules.
Glycogen storage diseases like Pompe's disease are due to a deficiency of the
lysosomal enzyme acid alpha-glucosidase, leading to glycogen accumulation.
10. Which of the following RNA types carries the genetic code from DNA to the
ribosome for protein synthesis?
A. tRNA
B. rRNA
C. mRNA
D. snRNA
Answer: C. mRNA
Rationale: Messenger RNA (mRNA) carries the transcribed genetic code from the
nucleus to the ribosome in the cytoplasm, where it directs protein synthesis. tRNA
carries amino acids. rRNA makes up the ribosome. snRNA is involved in splicing.
11. A patient with a malignant tumor has a biopsy showing cells of varying sizes
and shapes. This feature is referred to as:
A. Hyperplasia
B. Metaplasia
C. Anaplasia
D. Hypertrophy
Answer: C. Anaplasia
Rationale: Anaplasia is a hallmark of malignant tumors characterized by loss of
cellular differentiation, pleomorphism (varying sizes and shapes), and atypical
nuclei. Hyperplasia is increased number of cells. Metaplasia is a change from one
mature cell type to another. Hypertrophy is an increase in cell size.
