Consider statements about genetics: 1. A codon consists of three nucleotides. 2. The start codon is AUG. 3. Introns are coding sequences. Which are correct? MCQ with Answer and Explanation

Consider statements about genetics: 1. A codon consists of three nucleotides. 2. The start codon is AUG. 3. Introns are coding sequences. Which are correct?
A. 2 and 3 only
B. 1 and 3 only
C. 1 and 2 only
D. 1, 2 and 3
Answer: Option C
Solution (By JKExamLibrary)
The genetic code is read in triplets of nucleotides called codons, each specifying an amino acid. AUG is the universal start codon, which also codes for methionine. In eukaryotic genes, introns are non-coding intervening sequences that are spliced out, while exons are the coding sequences that remain in the mature mRNA. Thus, statements 1 and 2 are correct.

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