Chorophyll 'a' molecule at its carbon atom 3 of the pyrrole ring II has one of the following

Options

A. aldehyde group
B. methyl group
C. carboxyl group
D. megnesium

Explanation

To solve the question regarding the chlorophyll 'a' molecule at its carbon atom 3 of the pyrrole ring II, we will follow these steps:

### Step 1: Understand the Structure of Chlorophyll 'a'
Chlorophyll 'a' is a complex molecule that contains a porphyrin ring structure. This structure includes several pyrrole rings, which are five-membered rings containing nitrogen atoms.

### Step 2: Identify the Pyrrole Ring II
In the chlorophyll 'a' structure, locate pyrrole ring II. Each pyrrole ring has carbon atoms, and we need to focus on carbon atom 3 of this specific ring.

### Step 3: Analyze the Substituents on Carbon Atom 3
Look closely at the substituents attached to carbon atom 3 of pyrrole ring II. According to the structure of chlorophyll 'a', you will find that a methyl group (–CH3) is attached to this carbon atom.

### Step 4: Evaluate the Given Options
Now, we need to evaluate the options provided:
- **Aldehyde group (–CHO)**: Not present in the structure of chlorophyll 'a'.
- **Methyl group (–CH3)**: Present at carbon atom 3 of pyrrole ring II.
- **Carboxyl group (–COOH)**: Not present as chlorophyll 'a' is not acidic.
- **Magnesium (Mg)**: Present in the center of the chlorophyll molecule, but not at carbon atom 3 of the pyrrole ring.

### Step 5: Conclude the Correct Answer
Based on the analysis, the correct answer is that at carbon atom 3 of the pyrrole ring II in chlorophyll 'a', there is a methyl group.

### Final Answer:
The correct option is **methyl group**.

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