MCQ Collection
MDCAT Biology MCQs
Practice MDCAT Biology questions with answers and explanations.
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Correct Answer: B. Removal of the amino group by deamination
Explanation:
Deamination removes nitrogen from amino acids.
The remaining carbon skeleton can enter glycolysis or the Krebs cycle.
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Correct Answer: B. It supplies H and OH to split a bond
Explanation:
Hydrolysis uses a water molecule to break a covalent bond.
The products receive hydrogen and hydroxyl groups.
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Correct Answer: B. Increase the speed of impulse conduction
Explanation:
Myelin electrically insulates the axon.
Impulses jump between nodes of Ranvier by saltatory conduction.
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Correct Answer: C. They contain more energy-rich C-H bonds
Explanation:
Fats are more reduced than carbohydrates.
Their oxidation supplies more high-energy electrons to respiration.
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Correct Answer: C. It supplies H and OH to split a bond
Explanation:
Hydrolysis uses a water molecule to break a covalent bond.
The products receive hydrogen and hydroxyl groups.
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Correct Answer: C. Increase the speed of impulse conduction
Explanation:
Myelin electrically insulates the axon.
Impulses jump between nodes of Ranvier by saltatory conduction.
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Correct Answer: A. Reverse transcriptase
Explanation:
Reverse transcriptase copies viral RNA into DNA.
The viral DNA can then integrate into the host genome.
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Correct Answer: B. Reverse transcriptase
Explanation:
Reverse transcriptase copies viral RNA into DNA.
The viral DNA can then integrate into the host genome.
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Correct Answer: C. Opportunistic infections due to low CD4 count
Explanation:
Loss of helper T cells impairs immune coordination.
Normally controlled organisms can then cause serious disease.
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Correct Answer: D. Opportunistic infections due to low CD4 count
Explanation:
Loss of helper T cells impairs immune coordination.
Normally controlled organisms can then cause serious disease.
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Correct Answer: A. Opportunistic infections due to low CD4 count
Explanation:
Loss of helper T cells impairs immune coordination.
Normally controlled organisms can then cause serious disease.
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Correct Answer: A. Advanced immune deficiency caused by HIV infection
Explanation:
AIDS is the advanced stage of HIV infection.
Severe immune suppression permits opportunistic infections and cancers.
