MCQ Collection
MDCAT 2026 MCQs
Practice MDCAT 2026 questions with answers and explanations.
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Correct Answer: C. A three-nucleotide sequence on mRNA specifying an amino acid or stop signal
Explanation:
The genetic code is read in triplets.
Each codon has a defined meaning.
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Correct Answer: C. An alternative form of a gene
Explanation:
Alleles occupy the same locus on homologous chromosomes.
They may produce different trait variants.
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Correct Answer: D. A three-nucleotide sequence on mRNA specifying an amino acid or stop signal
Explanation:
The genetic code is read in triplets.
Each codon has a defined meaning.
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Correct Answer: D. The genetic makeup for one or more traits
Explanation:
Genotype refers to allele combinations.
Phenotype results from genotype and environment.
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Correct Answer: A. A three-nucleotide sequence on tRNA complementary to an mRNA codon
Explanation:
The anticodon pairs with the codon during translation.
This ensures delivery of the correct amino acid.
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Correct Answer: A. The genetic makeup for one or more traits
Explanation:
Genotype refers to allele combinations.
Phenotype results from genotype and environment.
Choose an option to check your answer.
Correct Answer: B. A three-nucleotide sequence on tRNA complementary to an mRNA codon
Explanation:
The anticodon pairs with the codon during translation.
This ensures delivery of the correct amino acid.
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Correct Answer: B. The genetic makeup for one or more traits
Explanation:
Genotype refers to allele combinations.
Phenotype results from genotype and environment.
Choose an option to check your answer.
Correct Answer: C. A three-nucleotide sequence on tRNA complementary to an mRNA codon
Explanation:
The anticodon pairs with the codon during translation.
This ensures delivery of the correct amino acid.
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Correct Answer: C. Observable characteristics of an organism
Explanation:
Phenotype includes structural, biochemical, and behavioral traits.
It is influenced by genes and environment.
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Correct Answer: A. Uracil
Explanation:
RNA uses uracil instead of thymine.
Uracil pairs with adenine.
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Correct Answer: B. RNA carrying coding information from DNA to ribosomes
Explanation:
MRNA contains codons specifying amino-acid sequence.
It is translated by ribosomes.
