Due to which pigment red algae are capable of surviving in deep sea :-

Options

A. Chlorophyll 'd'
B. Carotenes
C. Phycocyanin
D. Phycoerythrin

Answer

**Step-by-Step Solution:**

1. **Understanding the Environment**: Red algae are found in deep-sea environments where sunlight penetration is limited. The deeper you go into the ocean, the less light is available for photosynthesis.

2. **Role of Light in Photosynthesis**: Algae, like all plants, require light to perform photosynthesis, which is the process of converting light energy into chemical energy (food).

3. **Wavelengths of Light**: White light consists of various wavelengths, but not all wavelengths penetrate water effectively. In deep waters, shorter wavelengths (like red light) are absorbed quickly, while longer wavelengths (like blue light) can penetrate deeper.

4. **Pigments in Red Algae**: Red algae contain specific pigments that allow them to absorb the available light. The three main pigments present in red algae are:
- Chlorophyll-A
- Phycocyanin
- Phycoerythrin

5. **Importance of Phycoerythrin**: Among these pigments, phycoerythrin is particularly important because it absorbs blue light, which is the wavelength that penetrates deepest into the ocean. By absorbing this blue light, red algae can utilize the limited light available in deep sea environments for photosynthesis.

6. **Conclusion**: Therefore, the pigment that enables red algae to survive in deep sea conditions is **phycoerythrin**, as it allows them to effectively capture and use the blue light that penetrates deep into the water.

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