Question

If a tRNA molecule has an anticodon which reads AUG, what was the codon of the mRNA molecule?

CGU

TAC

TAG

UAC

Answer 1

Okay, so we're talking about......tRNA, and mRNA.

These are how tRNA and mRNA letters match up.

A goes with U
C goes with G

So...for example....

if the tRNA is.... (A C U),
then the mRNA will be (U G A)

Again,

A matches with U,
and C matches with G.

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So let's take a look at your problem.

The tRNA is (A U G).

Can you figure out the mRNA now?

Answer 2

was it ... CGU ? @InYourHead

Answer 3

No. Have you read my explanation?

Answer 4

Yes..
second guess is TAC
@InYourHead

Answer 5

You're just going down the option list. Stop guessing. I'll re-explain it.

Remember these two RULES:

A goes with U
G goes with C

Let me give you some examples:

If the ANTI-CODON is......(A A G)
then the CODON is..........(U U C)

Look at the two codons standing on top of each other.
Look at the way that they're matched up.

If A is on top,
U is right underneath it.
Because A goes with U.

If G is on top,
C is right underneath it.
Because G goes with C.

The two rules I gave you earlier. Remember them.

Here's another example:

If the ANTI-CODON is.....(G G U)
the CODON will be..........(C C A)

Look at the first codon, and all three of its letters.

The first letter in the ANTI-CODON is G.

What does G go with?
It goes with C.

That's why C is the first letter of the CODON, right underneath G.

The second letter in the ANTI-CODON is G. It goes with C.
The last letter in the ANTI-CODON is U. It goes with A.

SO, again....if the anti-codon is (G G U),
then the codon will be....(C C A).

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Now here's the real question.

What if the ANTI-CODON is (A U G) ?
What will the CODON, right underneath it, be?

Answer 6

OH !!!! UAC ! Because A = U , U = A , G = C
Wow.. you explained that really well :D

Answer 7

Yep! UAC.