Question

If a tRNA molecule has an anticodon which reads GCU, what will it match up with and what amino acid is it carrying?

It is carrying alanine and will match with a GCU codon on the mRNA.

It is carrying arginine and will match with a CGA codon on the mRNA.

It is carrying arginine and will match with a CGT codon on the DNA.

It is carrying no amino acid and will match with a UAG codon on the mRNA.

Help please?

Answer 1

I think it's A.

Answer 2

If the tRNA is (G C U),
then its mRNA partner will be (C G A).

That's because in the relationship between tRNA and mRNA...

A matches with U
G matches with C

So, let's look at the match again:

tRNA: G C U
mRNA: C G A

You see?

Take a look at this amino acid chart:
http://www.tritechresearch.com/shop//images/aachart.gif

We know that the mRNA codon is (C G A).
So, we need to find (C G A) on the chart.

If we look,
we can see that (C G A) comes together at (Arg),
which stands for Arginine.

That's what it's carrying.
Arginine.