`PS` II contains a non-chlorophyllous pigment in blue-green algae

Options

A. `beta`-carotene
B. Zeaxanthin
C. Phycocyanin
D. Cytochrome c.

Answer

To answer the question regarding which non-chlorophyllous pigment is present in Photosystem II (PS II) of blue-green algae, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components of Photosystem II**:
- Photosystem II (PS II) is a complex involved in the light-dependent reactions of photosynthesis. It contains chlorophyll and other pigments that assist in capturing light energy.

2. **Focus on Blue-Green Algae**:
- Blue-green algae, also known as cyanobacteria, are unique because they contain specific pigments that differ from those found in higher plants.

3. **Recognize the Main Pigment in Blue-Green Algae**:
- The primary chlorophyll pigment in blue-green algae is chlorophyll A. This pigment plays a crucial role in the photosynthetic process.

4. **Identify Non-Chlorophyllous Pigments**:
- In addition to chlorophyll A, blue-green algae contain other pigments. One significant non-chlorophyllous pigment present in these organisms is phycocyanin, which gives them their characteristic blue color.

5. **Evaluate the Options Provided**:
- The question likely provides several options for the non-chlorophyllous pigment. The options include:
- a) Beta carotene
- b) Zeaxanthin
- c) Phycocyanin
- d) Cytochrome C
- Among these options, phycocyanin is the only pigment that is non-chlorophyllous and is specifically found in blue-green algae.

6. **Select the Correct Answer**:
- Based on the analysis, the correct answer to the question is phycocyanin, as it is the non-chlorophyllous pigment involved in PS II of blue-green algae.

### Final Answer:
The non-chlorophyllous pigment in PS II of blue-green algae is **phycocyanin**.

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