MCAT Biology Question 8: Answer and Explanation
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Question: 8
8. Which of the following organelles is surrounded by a single membrane?
- A. Lysosomes
- B. Mitochondria
- C. Nuclei
- D. Ribosomes
Correct Answer: A
Explanation:
Lysosomes are vesicular organelles that digest material using hydrolytic enzymes. They are surrounded by a single membrane. Both mitochondria and nuclei are surrounded by double membranes, eliminating choices (B) and (C). Ribosomes must not be surrounded by membranes because they are found not only in eukaryotes, but also in prokaryotes, which lack any membrane-bound organelles, eliminating choice (D).