`C_2 H_4` is synthesised large amounts by -

Options

A. Shoot tip
B. Root tip
C. Young leaves
D. Tissue undergoing senescence and ripening fruits

Answer

To answer the question regarding where `C2H4` (ethylene) is synthesized in large amounts, we can break down the information provided in the transcript into a structured solution.

### Step-by-Step Solution:

1. **Understanding Ethylene (C2H4)**:
- Ethylene is a plant hormone known for its role in various physiological processes, including fruit ripening and senescence.

2. **Identifying Sources of Ethylene**:
- The transcript mentions two primary sources where ethylene is synthesized in large amounts:
- **Tissue undergoing senescence**: This refers to plant tissues that are aging or deteriorating. During this process, ethylene is produced to facilitate the breakdown of cells and tissues.
- **Ripening fruits**: Ethylene is also produced in significant quantities in fruits as they ripen. This gas acts as a signaling molecule that promotes the ripening process.

3. **Exclusion of Other Options**:
- The other options provided in the question (soot tip, root tip, young leaves) are associated with different plant hormones:
- **Soot tip and root tip**: These regions are known for the presence of auxins, which are involved in growth and elongation.
- **Young leaves**: These parts are associated with cytokinins, which promote cell division and growth.
- Therefore, these options do not synthesize ethylene in large amounts.

4. **Conclusion**:
- Based on the analysis, the correct answer to the question is that ethylene (`C2H4`) is synthesized in large amounts by **tissue undergoing senescence** and **ripening fruits**.

### Final Answer:
Ethylene (`C2H4`) is synthesized in large amounts by tissue undergoing senescence and ripening fruits.

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