Assertion.Cyanobacteria are photosynthetic blue-green algae with procaryotic structure.
Reason. They are green due to presence of chloroplasts.

Options

A. both true with reason being correct explanation
B. both true but reason not correct explanation
C. assertion true but reason is wrong
D. both wrong

Answer

To analyze the given assertion and reason, we will break down the information step by step.

### Step 1: Understanding the Assertion
The assertion states that "Cyanobacteria are photosynthetic blue-green algae with prokaryotic structure."

- **Cyanobacteria** are indeed classified as blue-green algae.
- They are photosynthetic organisms, meaning they can convert light energy into chemical energy.
- They possess a prokaryotic structure, which means they lack a defined nucleus and membrane-bound organelles.

### Step 2: Understanding the Reason
The reason states that "They are green due to the presence of chloroplasts."

- This statement is misleading. While cyanobacteria are photosynthetic and can appear green due to the presence of chlorophyll, they do not have chloroplasts.
- Instead, they have thylakoid membranes where photosynthesis occurs, which is a characteristic of prokaryotic organisms.

### Step 3: Evaluating the Truth of Assertion and Reason
- The assertion is **true**: Cyanobacteria are indeed photosynthetic blue-green algae with a prokaryotic structure.
- The reason is **false**: They are not green due to the presence of chloroplasts, as they do not possess chloroplasts.

### Conclusion
Based on the evaluation:
- The assertion is true, but the reason is false. Therefore, the correct answer is: "Assertion true but reason is wrong."

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