MCQ Collection
MDCAT Biology MCQs
Practice MDCAT Biology questions with answers and explanations.
Choose an option to check your answer.
Correct Answer: B. Diffusion of water across a selectively permeable membrane
Explanation:
Water moves toward the side with higher effective solute concentration.
Osmosis affects cell volume and turgor.
Choose an option to check your answer.
Correct Answer: C. Cytosol plus organelles outside the nucleus
Explanation:
Cytoplasm includes the cytosol and suspended structures.
Many metabolic reactions occur there.
Choose an option to check your answer.
Correct Answer: C. Diffusion of water across a selectively permeable membrane
Explanation:
Water moves toward the side with higher effective solute concentration.
Osmosis affects cell volume and turgor.
Choose an option to check your answer.
Correct Answer: D. Cytosol plus organelles outside the nucleus
Explanation:
Cytoplasm includes the cytosol and suspended structures.
Many metabolic reactions occur there.
Choose an option to check your answer.
Correct Answer: D. Diffusion of water across a selectively permeable membrane
Explanation:
Water moves toward the side with higher effective solute concentration.
Osmosis affects cell volume and turgor.
Choose an option to check your answer.
Correct Answer: A. Chloroplast
Explanation:
Chloroplasts contain chlorophyll and photosynthetic membranes.
They convert light energy into chemical energy.
Choose an option to check your answer.
Correct Answer: A. Cytosol plus organelles outside the nucleus
Explanation:
Cytoplasm includes the cytosol and suspended structures.
Many metabolic reactions occur there.
Choose an option to check your answer.
Correct Answer: A. Passive movement through membrane proteins down a concentration gradient
Explanation:
Channels and carriers help polar or charged substances cross membranes.
No direct energy input is required.
Choose an option to check your answer.
Correct Answer: B. Chloroplast
Explanation:
Chloroplasts contain chlorophyll and photosynthetic membranes.
They convert light energy into chemical energy.
Choose an option to check your answer.
Correct Answer: B. A network of protein filaments supporting cell shape and movement
Explanation:
The cytoskeleton includes microtubules, microfilaments, and intermediate filaments.
It supports transport, division, and movement.
Choose an option to check your answer.
Correct Answer: B. Passive movement through membrane proteins down a concentration gradient
Explanation:
Channels and carriers help polar or charged substances cross membranes.
No direct energy input is required.
Choose an option to check your answer.
Correct Answer: C. Storage and maintenance of turgor pressure
Explanation:
The central vacuole stores water, ions, pigments, and wastes.
Its pressure helps support plant tissues.
