Campbell Biology Chapter 16-17

Last update by hturek on 10/21/2014
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A particular triplet of bases in the coding sequence of DNA is AAA. The anticodon on the tRNA that binds the mRNA codon is

A) TTT.

B) UUA.

C) UUU.

D) AAA.

E) either UAA or TAA, depending on first base wobble.

Answer:

C) UUU

This is incorrect, if the coding sequence on DNA is AAA, then the mRNA transcript will read UUU and then the anticodon on the tRNA that binds to it will read AAA, so the correct answer is D

No, the answer C is correct. If the coding DNA is AAA, the template DNA is TTT, so the mRNA, which codes the template strand is also AAA, which is the codon. The anticodon is therefore UUU

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