Red eye spot (stigma) is meant for

Options

A. movement
B. vision
C. photoreception
D. photosynthesis

Answer

### Step-by-Step Solution:

1. **Understanding the Red Eye Spot (Stigma)**:
- The red eye spot, also known as stigma, is a specialized structure found in certain photosynthetic organisms, particularly in euglenoids and some flagellates of green algae.

2. **Identifying the Nature of the Eye Spot**:
- The eye spot is classified as a photoreceptive organelle. This means it plays a role in detecting light.

3. **Function of the Red Eye Spot**:
- The primary function of the red eye spot is to sense light. It helps the organism determine the direction and intensity of light in its environment.

4. **Response to Light**:
- Based on the information sensed by the eye spot, the organism can respond by swimming toward the light (positive phototaxis) or away from it (negative phototaxis).

5. **Composition of the Eye Spot**:
- The eye spot is composed of photoreceptors and contains bright orange-red pigment granules, which contribute to its color and function.

6. **Conclusion**:
- Therefore, the red eye spot (stigma) is primarily meant for photoreception, allowing the organism to interact with its light environment effectively.

### Final Answer:
The red eye spot (stigma) is meant for photoreception.

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