Structures of the Cell Quick Check.

Question

If the sequence of bases on the MRNA codon is AUU, what would be the sequence of bases on the opposite strand assembled by the tRNA?
1. UUA
2. UAA
3. ATT
4. TAA

Answer 1

To determine the sequence of bases on the tRNA that corresponds to the mRNA codon AUU, we need to find the complementary sequence.

The mRNA codon AUU would pair with tRNA anticodon that is complementary to it. The base pairing rules are:

• Adenine (A) pairs with Uracil (U) in RNA.
• Uracil (U) pairs with Adenine (A).
• Cytosine (C) pairs with Guanine (G).
• Guanine (G) pairs with Cytosine (C).

Given the mRNA codon AUU:

• A pairs with U
• U pairs with A
• U pairs with A

Thus, the tRNA anticodon that pairs with AUU will be UAA.

Therefore, the correct answer is: 2. UAA