Tunica and corpus are constituents of

Options

A. root apex
B. shoot apex
C. mass meristem
D. all of the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms**: The question asks about "Tunica" and "Corpus." These terms are related to plant anatomy, specifically in the context of the shoot apex.

2. **Identifying the Theory**: The Tunica-Corpus theory was proposed by Schmitz in 1924. This theory explains the structure of the shoot apex in angiosperms.

3. **Defining the Zones**: According to the Tunica-Corpus theory, the shoot apex is divided into two distinct zones:
- **Tunica**: This is the peripheral zone, which is primarily involved in the growth of the outer layers of the shoot. It divides mainly in the anticlinal plane (perpendicular to the surface).
- **Corpus**: This is the central zone, which is responsible for the growth of the inner tissues. It can divide in various planes, not limited to the anticlinal plane.

4. **Conclusion**: Based on the information provided, Tunica and Corpus are constituents of the shoot apex in angiosperms.

5. **Final Answer**: Therefore, the answer to the question is that Tunica and Corpus are constituents of the **shoot apex**.

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