Question

A possible sequence of nucleotides in the template strand of DNA that would code for the polypeptide sequence NH2-phe-leu-ile-val-COOH would be

- 5' AUG-CTG-CAG-TAT 3'.
- 3' AAA-AAT-ATA-ACA 5'.
-3' AAC-GAC-GUC-AUA 5'.
-5' TTG-CTA-CAG-TAG 3'.
-3' AAA-GAA-TAA-CAA 5'.

Answer 1

To determine the sequence of mRNA complementary to a DNA strand, nucleotides are paired following base-pairing rules with uracil pairing with adenine. The resulting mRNA codons are then used to translate into a specific amino acid sequence, following the genetic code.

Step-by-step explanation:

The question involves understanding DNA transcription and translation processes which are fundamental in molecular biology. Given a DNA template strand, the sequence of mRNA that is complementary to it can be determined by replacing the DNA base pairs with their RNA complements (A with U, T with A, C with G, and G with C). Transcription follows the base-pairing rule, but with uracil (U) in RNA pairing with adenine (A) in DNA.

For the DNA sequence 3'...GCT GTC AAA TTC GAT...5', the complementary mRNA strand would be 5'...CGA CAG UUU AAG CUA...3'. Each group of three nucleotides in mRNA, known as a codon, corresponds to a specific amino acid. Using a codon chart, these mRNA codons translate into a polypeptide sequence with a specific amino acid sequence. For example, AUG in mRNA codes for the amino acid methionine, which is often the start codon for protein synthesis.