Chl a, Chl d and phycoerythrin occur in

Options

A. Chlorophyceae
B. Bacillariophyceae
C. Cyanophyceae
D. Rhodophyceae.

Answer

To answer the question regarding where chlorophyll a, chlorophyll d, and phycoerythrin occur, we can follow these steps:

### Step 1: Understand the Pigments
- **Chlorophyll a** is a common pigment found in many photosynthetic organisms.
- **Chlorophyll d** is less common and is primarily found in certain types of red algae.
- **Phycoerythrin** is a pigment that gives red algae their color and is involved in photosynthesis.

### Step 2: Analyze the Options
1. **Chlorophyceae**: This group includes green algae, which primarily contain chlorophyll a and b. They do not typically have chlorophyll d or phycoerythrin.
2. **Bacillariophyceae**: This group includes diatoms, which contain chlorophyll a and c. They do not have chlorophyll d or phycoerythrin.
3. **Cyanophyceae**: Also known as blue-green algae, they contain chlorophyll a and phycocyanin, but they do not have chlorophyll d.
4. **Rhodophyceae**: This group includes red algae, which contain chlorophyll a, chlorophyll d, and phycoerythrin.

### Step 3: Identify the Correct Group
From the analysis:
- **Chlorophyceae** does not contain chlorophyll d or phycoerythrin.
- **Bacillariophyceae** does not contain chlorophyll d or phycoerythrin.
- **Cyanophyceae** does not contain chlorophyll d.
- **Rhodophyceae** contains chlorophyll a, chlorophyll d, and phycoerythrin.

### Conclusion
The correct answer is **Rhodophyceae** (red algae), as it is the only group that contains all three pigments mentioned in the question.

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