Genetic Code: Val-tRNA Val - Anticodon Selection

[VanessaN]

Homework Statement

Val-tRNA val is the tRNA that carries valine to the ribosome during translation. Which of the following sequences gives an appropriate anticodon for this tRNA?

A. CAU
B. AUC
C. UAC
D. GUG

Homework Equations

There are four different codons for Valine: GUU, GUC, GUA, and GUG.

The Attempt at a Solution

The answer is C, but I'm just wondering how to approach problems like this in the future.
Since we're looking for the anticodon, and DNA is read 5'---> 3', we would have to flip all 4 codons for Val:
UUG, CUG, AUG, GUG.
Then would we follow complementary base pairing rules to get:
AAC, GAC, UAC, CAC

That way, we get the correct answer, but I'm just wondering if I have the correct method down or if somebody could help explain to me why this is the reason its done this way? Thank you!

 

[jedishrfu]

You could have eliminated a couple of choices like D right because it is Val-tRNA.

Choice B has a matching U in the middle.

So you're left with choice A or C and your analysis then applies to determine which one is the winner.

Here's a discussion on codons:

http://en.wikipedia.org/wiki/Genetic_code

 

[VanessaN]

You could have eliminated a couple of choices like D right because it is Val-tRNA.

Choice B has a matching U in the middle.

So you're left with choice A or C and your analysis then applies to determine which one is the winner.

Here's a discussion on codons:

http://en.wikipedia.org/wiki/Genetic_code

Thanks!