Biology · Chromosomes and DNA
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The complementary mRNA for the DNA triplet GAT would read:
- A
CTA
- B
CUA
- C
CTG
- D
CTC
In mRNA, G pairs with C
A pairs with U
T pairs with A.
Therefore, The triplet GAT will have CUA
a) CTA: In DNA, adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G). However, in RNA, uracil (U) replaces thymine (T). So, the complementary mRNA sequence for the DNA triplet GAT would be "CUA." This is the correct answer.
b) CUA: This option is the correct answer. It corresponds to the complementary mRNA sequence for the DNA triplet GAT. In mRNA, cytosine (C) pairs with guanine (G), just like in DNA, and adenine (A) pairs with uracil (U) instead of thymine (T).
c) CTG: This sequence is not complementary to the DNA triplet GAT. In DNA, guanine (G) pairs with cytosine (C), so the complementary mRNA sequence would have cytosine (C) pairing with guanine (G), which is not the case in this option.
d) CTC: This sequence is not complementary to the DNA triplet GAT. Like the previous option, the correct complementary mRNA sequence for the DNA triplet GAT would have "CUA" as its corresponding sequence.
Tagged under Biology · Chromosomes and DNA · 2000