Below is the sequence from the 3′ end of an mRNA. 5′-CCGUUACCAGGCCUCAUUAUUGGUAACGGAAAAAAAAAAAAAA-3′ If you were told that this sequence contains the stop codon for the protein encoded by this mRNA, what is the anticodon on the tRNA in the P site of the ribosome when release factor binds to the A site?
A) 5'-CCA-3'
B) 5'-CCG-3'
C) 5'-UGG-3'
D) 5'-UUA-3'

Respuesta :

Answer:

D

Explanation:

The mRNA sequence given is in the 5' to 3' direction, the anticodon on the tRNA is in the opposite direction to the mRNA so would be in the 3' to 5' direction.

First we have to find the stop codon in the mRNA which is UAA, UAG or UGA.

5′-CCGUUACCAGGCCUCAUUAUUGGUAACGGAAAAAAAAAAAAAA-3′.

Now that we have found the stop codon, we can determine what the anticodon is by using the complementary sequence to the stop codon. This will be 3'-AUU-5', because A is complementary to U and G is complementary to C. The answers are given in the 5' to 3' direction, therefore we turn it around so that it is 5'-UUA-3' and we have our answer.