Chlorophyll consists of

Options

A. A head of phytol and tail of four pyrrole rings
B. A head of linked carbons and tail of four pyrrole rings
C. A head of four pyrrole rings and tail of linked nitrogens
D. A head of four pyrrole rings and an alcoholic phytol tail.

Answer

**Step-by-step Solution:**

1. **Understanding Chlorophyll**: Chlorophyll is a crucial pigment found in plants that plays a significant role in photosynthesis by absorbing light, which imparts a green color to the plants.

2. **Structure of Chlorophyll**: Chlorophyll consists of two main parts: a head and a tail.

3. **The Head**:
- The head of chlorophyll is known as the porphyrin ring.
- It is composed of four pyrrole rings that are interconnected by methine bridges.
- At the center of the porphyrin ring, there is a magnesium ion (Mg) surrounded by nitrogen atoms from the pyrrole rings.

4. **The Tail**:
- The tail of chlorophyll is a long chain of alcohol known as phytol.
- This phytol tail is hydrophobic, which helps anchor the chlorophyll molecule in the thylakoid membranes of chloroplasts.

5. **Distinction Between Chlorophyll A and B**:
- Chlorophyll A has a methyl group (-CH3) at a specific position in the structure, while chlorophyll B has an aldehyde group (-CHO) at the same position.

6. **Evaluating Options**:
- Option A states "a head of phytol and tail of 4-pyrrole rings" - Incorrect, as the head is made of pyrrole rings, not phytol.
- Option B states "a head of linked carbons and tail of 4-pyrrole rings" - Incorrect, as the head is made of pyrrole rings, not linked carbons.
- Option C states "a head of 4-pyrrole rings and tail of linked nitrogens" - Incorrect, as the tail is not made of linked nitrogens.
- Option D states "a head of 4-pyrrole rings and alcoholic phytol tail" - Correct, as this accurately describes the structure of chlorophyll.

7. **Conclusion**: The correct answer is Option D: "a head of 4-pyrrole rings and alcoholic phytol tail."

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