Question

Use the following table to answer the question:

This table shows the codons found in messenger RNA. Using this information, what sequence of nucleotides in the template strand of DNA could code for the polypeptide sequence Phe-Ser-Gln?
UUC-UCU-CAA
AAG-AGA-GTT
TTC-TCT-CAA
AAG-AGA-GUU

Answer 1

The answer is UUC-UCU-CAA

Step-by-step explanation:

According to the table there are different sequences of nucleotides that can code for Phe-Ser-Gin.

• Phe can be made by UUC or UUU
• Ser can be made by UCU, UCC, UCA, or UCG
• Gin can be made by CAA or CAG

Also, T is not in RNA, it is replaced by U. This makes option AAG-AGA-GTT (option B) and TTC-TCT-CAA (option C) incorrect.

Option D does not have the sequences for Phe-Ser-Gin, so it is also incorrect.

Option A - UUC-UCU-CAA is the only option that has a polypeptide sequence for Phe-Ser-Gin. This is the correct answer.