MCQ Collection
MDCAT 2026 MCQs
Practice MDCAT 2026 questions with answers and explanations.
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Correct Answer: A. A protein produced by B-cell descendants that binds a specific antigen
Explanation:
Antibodies can neutralize, opsonize, or activate complement.
Their binding sites are antigen-specific.
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Correct Answer: B. A viral cycle ending with host-cell lysis and virus release
Explanation:
Viral components are synthesized and assembled inside the host.
The host cell then breaks open.
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Correct Answer: B. Produce antibody responses and memory B cells
Explanation:
Activated B cells can become plasma cells.
Plasma cells secrete antibodies.
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Correct Answer: C. A viral genome integrates into or persists with host DNA before activation
Explanation:
The viral genome may be copied with the host chromosome.
It can later enter the lytic cycle.
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Correct Answer: C. Produce antibody responses and memory B cells
Explanation:
Activated B cells can become plasma cells.
Plasma cells secrete antibodies.
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Correct Answer: D. A viral genome integrates into or persists with host DNA before activation
Explanation:
The viral genome may be copied with the host chromosome.
It can later enter the lytic cycle.
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Correct Answer: D. Produce antibody responses and memory B cells
Explanation:
Activated B cells can become plasma cells.
Plasma cells secrete antibodies.
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Correct Answer: A. A noncellular infectious particle requiring a host cell to reproduce
Explanation:
Viruses contain genetic material inside a protein coat.
Some also possess a lipid envelope.
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Correct Answer: A. A viral genome integrates into or persists with host DNA before activation
Explanation:
The viral genome may be copied with the host chromosome.
It can later enter the lytic cycle.
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Correct Answer: A. Kill infected or abnormal host cells
Explanation:
Cytotoxic T cells recognize specific antigens on cell surfaces.
They induce target-cell death.
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Correct Answer: B. A noncellular infectious particle requiring a host cell to reproduce
Explanation:
Viruses contain genetic material inside a protein coat.
Some also possess a lipid envelope.
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Correct Answer: B. Rapid nonspecific defense present from birth
Explanation:
Innate immunity includes barriers, inflammation, phagocytes, and complement.
It responds quickly to broad pathogen patterns.
