In eukaryotes, translation of mRNA into a polypeptide is initiated by

Options

A. UGA
B. UAA
C. UAG
D. AUG

Answer

To solve the question regarding the initiation of translation in eukaryotes, we can follow these steps:

### Step 1: Understand the Question
The question asks about the initiation of translation of mRNA into a polypeptide in eukaryotes. We need to identify which codon is responsible for this initiation.

### Step 2: Identify the Start Codon
In molecular biology, the start codon is the specific codon that signals the beginning of translation. In eukaryotes, this start codon is universally recognized.

### Step 3: Recall the Start Codon
The start codon in eukaryotes is known to be AUG. This codon codes for the amino acid methionine, which is the first amino acid incorporated into a polypeptide chain during translation.

### Step 4: Analyze the Options
The options provided are:
- A) UGA
- B) UAA
- C) UAG
- D) AUG

Among these options, UGA, UAA, and UAG are known as stop codons, which signal the termination of translation, not the initiation.

### Step 5: Select the Correct Answer
Since AUG is the only codon listed that is known to initiate translation in eukaryotes, we can conclude that the correct answer is option D, which is AUG.

### Final Answer
The translation of mRNA into a polypeptide in eukaryotes is initiated by **option D: AUG**.

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