Callus is not produced in

Options

A. Wound
B. Tissue culture
C. Suspension culture
D. Sexual reproduction.

Answer

**Step-by-Step Solution:**

1. **Understanding Callus Formation:**
- Callus is a mass of undifferentiated cells that forms in response to injury or in tissue culture. It is primarily composed of plant cells that are in a state of division and growth.

2. **Analyzing the Options:**
- **Wood:** In the case of wounds in plants, callus formation occurs as part of the healing process. Therefore, callus is produced in wood.
- **Tissue Culture:** In tissue culture, especially from meristematic tissues, callus is intentionally induced for plant propagation. Thus, callus is produced in tissue culture.
- **Suspension Culture:** In suspension culture, cells are cultured in a liquid medium, and as they divide, they can also form callus. Hence, callus is produced in suspension culture.
- **Sexual Reproduction:** During sexual reproduction, male and female gametes combine to form a zygote. This process does not involve the formation of callus.

3. **Conclusion:**
- Based on the analysis, the option where callus is not produced is **sexual reproduction**.

**Final Answer: Sexual reproduction.**

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