`mRNA overset(AUG UUU AUG C CU GUU UCU UA A)to`
Polypeptide Met-Phe-Met-Pro-Val-Ser
Which codons respectively code for proline and valine amino acids in the given polypeptide chain, respectively ?

Options

A. C CU and GUU
B. GUU and UCU
C. UCU and UA A
D. GUU and C CU

Answer

To solve the question of which codons respectively code for proline and valine in the given polypeptide chain derived from the mRNA sequence, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the mRNA Sequence**:
The given mRNA sequence is: AUG UUU AUG CCU GUU UCU UAA.

2. **Translate the mRNA Sequence into Codons**:
The mRNA sequence is read in triplets (codons). The codons from the sequence are:
- AUG
- UUU
- AUG
- CCU
- GUU
- UCU
- UAA

3. **Determine the Corresponding Amino Acids**:
Using the genetic code, we can translate each codon into its corresponding amino acid:
- AUG → Methionine (Met)
- UUU → Phenylalanine (Phe)
- AUG → Methionine (Met)
- CCU → Proline (Pro)
- GUU → Valine (Val)
- UCU → Serine (Ser)
- UAA → Stop codon

4. **Identify the Codons for Proline and Valine**:
From the translated amino acids, we can see:
- Proline (Pro) is coded by the codon **CCU**.
- Valine (Val) is coded by the codon **GUU**.

5. **Conclusion**:
Therefore, the codons that respectively code for proline and valine in the given polypeptide chain are:
- Proline: **CCU**
- Valine: **GUU**

### Final Answer:
- The codon for proline is **CCU** and the codon for valine is **GUU**.

---