MCQ Collection
MDCAT 2026 MCQs
Practice MDCAT 2026 questions with answers and explanations.
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Correct Answer: B. 10
Explanation:
A d subshell contains five orbitals.
At two electrons per orbital, it holds ten electrons.
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Correct Answer: C. Glycerol joined to three fatty acids
Explanation:
Triglycerides are major energy-storage lipids.
They form through ester bonds.
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Correct Answer: C. Electrons fill lower-energy orbitals before higher-energy ones
Explanation:
The Aufbau principle guides ground-state configurations.
Actual filling order follows orbital energies.
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Correct Answer: D. A fatty acid with no carbon-carbon double bonds
Explanation:
Saturated fatty acids are fully saturated with hydrogen.
They are often solid at room temperature.
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Correct Answer: D. Electrons occupy equal-energy orbitals singly before pairing
Explanation:
Hund's rule minimizes electron repulsion in degenerate orbitals.
Unpaired electrons have parallel spins before pairing.
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Correct Answer: A. A glucose-storage polysaccharide in animals
Explanation:
Glycogen is stored mainly in liver and muscle.
It can be broken down to release glucose.
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Correct Answer: B. A glucose-storage polysaccharide in animals
Explanation:
Glycogen is stored mainly in liver and muscle.
It can be broken down to release glucose.
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Correct Answer: C. A glucose-storage polysaccharide in animals
Explanation:
Glycogen is stored mainly in liver and muscle.
It can be broken down to release glucose.
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Correct Answer: D. A glucose-storage polysaccharide in plants
Explanation:
Plants store glucose mainly as starch.
It consists of amylose and amylopectin.
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Correct Answer: A. A glucose-storage polysaccharide in plants
Explanation:
Plants store glucose mainly as starch.
It consists of amylose and amylopectin.
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Correct Answer: B. A glucose-storage polysaccharide in plants
Explanation:
Plants store glucose mainly as starch.
It consists of amylose and amylopectin.
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Correct Answer: C. A structural polysaccharide in plant cell walls
Explanation:
Cellulose consists of beta-glucose units.
Humans lack enzymes to digest its beta linkages.
