Which of the following has magnesium?

Chlorophyll

The correct answer is option 3. chlorophyll.

Let us delve into why chlorophyll contains magnesium and what distinguishes it from the other options:

Chlorophyll is a green pigment essential for photosynthesis in plants, algae, and cyanobacteria. Chlorophyll contains a porphyrin ring structure, which is a large, cyclic compound that can bind metal ions at its center.

Magnesium Center: In chlorophyll, magnesium (Mg²⁺) is the central metal ion in the porphyrin ring. This central magnesium ion plays a crucial role in the molecule’s ability to absorb light and facilitate the conversion of light energy into chemical energy during photosynthesis.

Photosynthesis: The magnesium ion in chlorophyll is vital for capturing light energy and converting it into chemical energy, which plants use to produce glucose and oxygen from carbon dioxide and water.

Other Options

1. Carbonic Anhydrase:

This enzyme contains zinc (Zn²⁺), not magnesium. Zinc is crucial for the enzyme’s catalytic activity, which helps in the conversion of carbon dioxide to carbonic acid and vice versa.

2. Haemocyanin:

Haemocyanin is an oxygen-carrying molecule found in the blood of some arthropods and mollusks. It contains copper (Cu) ions, which are involved in binding and transporting oxygen. Copper is central to its structure, not magnesium.

4. Vitamin \(B_{12}\):

Contains Cobalt**: Vitamin \(B_{12}\), also known as cobalamin, contains cobalt (Co) at its core. Cobalt is essential for the vitamin’s biological functions, including DNA synthesis and red blood cell formation.

Summary

Chlorophyll contains magnesium as a central component of its porphyrin ring structure. This magnesium ion is crucial for its role in photosynthesis, distinguishing it from carbonic anhydrase (which contains zinc), haemocyanin (which contains copper), and vitamin B12 (which contains cobalt)