MCQ Collection
MDCAT Biology MCQs
Practice MDCAT Biology questions with answers and explanations.
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Correct Answer: D. Formation of a bond by removal of water
Explanation:
Dehydration reactions join monomers into larger molecules.
A water molecule is released during bond formation.
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Correct Answer: A. Small independently replicating DNA molecules in many bacteria
Explanation:
Plasmids often carry accessory genes such as antibiotic resistance.
They can sometimes move between cells.
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Correct Answer: B. Development of structures and functions suited to a particular role
Explanation:
Different genes are expressed in different cell types.
This creates specialized structures and functions.
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Correct Answer: C. Development of structures and functions suited to a particular role
Explanation:
Different genes are expressed in different cell types.
This creates specialized structures and functions.
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Correct Answer: D. Development of structures and functions suited to a particular role
Explanation:
Different genes are expressed in different cell types.
This creates specialized structures and functions.
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Correct Answer: A. Separation of the plant cell membrane from the wall after water loss
Explanation:
Plasmolysis occurs in a hypertonic environment.
The vacuole shrinks and the membrane pulls inward.
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Correct Answer: A. A high surface-area-to-volume ratio supports efficient exchange
Explanation:
As a cell grows, volume increases faster than surface area.
Small size improves transport of nutrients, gases, and wastes.
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Correct Answer: B. Bacterial and archaeal cells
Explanation:
Prokaryotes lack a membrane-bound nucleus.
Their DNA is located in a nucleoid region.
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Correct Answer: B. A high surface-area-to-volume ratio supports efficient exchange
Explanation:
As a cell grows, volume increases faster than surface area.
Small size improves transport of nutrients, gases, and wastes.
Choose an option to check your answer.
Correct Answer: C. Bacterial and archaeal cells
Explanation:
Prokaryotes lack a membrane-bound nucleus.
Their DNA is located in a nucleoid region.
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Correct Answer: C. A high surface-area-to-volume ratio supports efficient exchange
Explanation:
As a cell grows, volume increases faster than surface area.
Small size improves transport of nutrients, gases, and wastes.
Choose an option to check your answer.
Correct Answer: D. Bacterial and archaeal cells
Explanation:
Prokaryotes lack a membrane-bound nucleus.
Their DNA is located in a nucleoid region.