MCQ Collection
MDCAT Biology MCQs
Practice MDCAT Biology questions with answers and explanations.
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Correct Answer: C. Lysosome
Explanation:
Lysosomes break down macromolecules and damaged cell parts.
Their enzymes work best in an acidic environment.
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Correct Answer: D. They arise from pre-existing cells
Explanation:
Modern cell theory states that cells come from existing cells.
Cell division provides continuity of life.
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Correct Answer: D. Ribosomal RNA synthesis and ribosome subunit assembly
Explanation:
The nucleolus is a dense region inside the nucleus.
It produces rRNA and assembles ribosomal subunits.
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Correct Answer: D. Lysosome
Explanation:
Lysosomes break down macromolecules and damaged cell parts.
Their enzymes work best in an acidic environment.
Choose an option to check your answer.
Correct Answer: A. They arise from pre-existing cells
Explanation:
Modern cell theory states that cells come from existing cells.
Cell division provides continuity of life.
Choose an option to check your answer.
Correct Answer: A. Ribosomal RNA synthesis and ribosome subunit assembly
Explanation:
The nucleolus is a dense region inside the nucleus.
It produces rRNA and assembles ribosomal subunits.
Choose an option to check your answer.
Correct Answer: A. Production of ATP through aerobic respiration
Explanation:
Mitochondria convert energy from nutrients into ATP.
They contain their own DNA and ribosomes.
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Correct Answer: B. They arise from pre-existing cells
Explanation:
Modern cell theory states that cells come from existing cells.
Cell division provides continuity of life.
Choose an option to check your answer.
Correct Answer: B. Ribosome
Explanation:
Ribosomes translate mRNA into polypeptide chains.
They occur freely in cytoplasm or attached to rough ER.
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Correct Answer: B. Production of ATP through aerobic respiration
Explanation:
Mitochondria convert energy from nutrients into ATP.
They contain their own DNA and ribosomes.
Choose an option to check your answer.
Correct Answer: C. Plasma membrane
Explanation:
The plasma membrane is selectively permeable.
It regulates exchange between the cell and its environment.
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Correct Answer: C. Ribosome
Explanation:
Ribosomes translate mRNA into polypeptide chains.
They occur freely in cytoplasm or attached to rough ER.
