MCQ Collection
MDCAT 2026 MCQs
Practice MDCAT 2026 questions with answers and explanations.
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Correct Answer: C. Fusion of haploid gametes to form a diploid zygote
Explanation:
Fertilization restores the diploid chromosome number.
The resulting zygote begins development.
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Correct Answer: D. Fusion of haploid gametes to form a diploid zygote
Explanation:
Fertilization restores the diploid chromosome number.
The resulting zygote begins development.
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Correct Answer: A. The first diploid cell formed after fertilization
Explanation:
The zygote contains genetic material from both parents.
It divides by mitosis during early development.
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Correct Answer: B. The first diploid cell formed after fertilization
Explanation:
The zygote contains genetic material from both parents.
It divides by mitosis during early development.
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Correct Answer: C. The first diploid cell formed after fertilization
Explanation:
The zygote contains genetic material from both parents.
It divides by mitosis during early development.
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Correct Answer: D. A cell with two sets of chromosomes
Explanation:
Diploid cells contain homologous chromosome pairs.
Most human body cells are diploid.
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Correct Answer: A. Homologous chromosomes pair and crossing over may occur
Explanation:
Synapsis forms homologous pairs called bivalents.
Crossing over exchanges DNA between nonsister chromatids.
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Correct Answer: A. Failure of chromosomes to separate normally
Explanation:
Nondisjunction can occur in meiosis or mitosis.
It produces cells with abnormal chromosome numbers.
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Correct Answer: B. Exchange of DNA between nonsister chromatids of homologous chromosomes
Explanation:
Crossing over occurs during prophase I.
It produces new allele combinations.
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Correct Answer: B. Failure of chromosomes to separate normally
Explanation:
Nondisjunction can occur in meiosis or mitosis.
It produces cells with abnormal chromosome numbers.
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Correct Answer: C. Exchange of DNA between nonsister chromatids of homologous chromosomes
Explanation:
Crossing over occurs during prophase I.
It produces new allele combinations.
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Correct Answer: C. Failure of chromosomes to separate normally
Explanation:
Nondisjunction can occur in meiosis or mitosis.
It produces cells with abnormal chromosome numbers.
