In chorophyll, structure four pyrrole ring are united with Mg by their atoms of

Options

A. C
B. H
C. O
D. N.

Answer

To answer the question regarding the structure of chlorophyll and how the four pyrrole rings are united with magnesium, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chlorophyll Structure**:
- Chlorophyll is a green pigment found in plants that plays a crucial role in photosynthesis. It consists of a porphyrin ring structure made up of four pyrrole rings.

2. **Identifying the Central Atom**:
- In the center of the chlorophyll molecule, there is a magnesium (Mg) ion. This magnesium ion is essential for the chlorophyll's function in capturing light energy.

3. **Examining the Pyrrole Rings**:
- Each of the four pyrrole rings in chlorophyll contains nitrogen atoms. Specifically, each pyrrole ring has one nitrogen atom.

4. **Connection to Magnesium**:
- The four nitrogen atoms from the pyrrole rings are coordinated to the magnesium ion. This coordination is what unites the pyrrole rings with the magnesium.

5. **Conclusion**:
- Therefore, the atoms that unite the four pyrrole rings with magnesium in chlorophyll are nitrogen atoms.

### Final Answer:
The correct answer is **nitrogen**.

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