Question

the amino acid serine is coded by the mrna codon agu. what is the base sequence of the dna gene that originally produced this mrna codon? (1 point)
o agu
o tca
o uca
o tcc

Explanation:

Step1: Recall base - pairing rules

In transcription, DNA is transcribed into mRNA. The base - pairing rules are: A (adenine) in DNA pairs with U (uracil) in mRNA, T (thymine) in DNA pairs with A (adenine) in mRNA, G (guanine) in DNA pairs with C (cytosine) in mRNA, and C (cytosine) in DNA pairs with G (guanine) in mRNA.

Step2: Determine DNA sequence from mRNA

Given the mRNA codon AGU. A in mRNA corresponds to T in DNA, G in mRNA corresponds to C in DNA, and U in mRNA corresponds to A in DNA. So the DNA sequence is TCA.

Answer:

TCA