Tigellum is

Options

A. A.a modified leaf
B. B.embryonal axis
C. C.a type of tendril
D. D.edible part in litchi

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Tigellum":**
- Tigellum refers to a specific part of the plant embryo. It is essential to know its role in the structure of the seed.

2. **Identifying the Options:**
- The options provided are:
a. Modified leaf
b. Embryonal axis
c. Type of tendril
d. Edible part of litchi

3. **Analyzing the Definition:**
- The tigellum is described as the main axis of the embryo. This indicates that it is not a leaf or a tendril but rather a central structure in the embryonic development of a plant.

4. **Understanding its Structure:**
- The tigellum connects the cotyledons (the seed leaves) to the embryonal axis. It is located at the cotyledonary node, which further supports the idea that it is part of the embryonic structure.

5. **Identifying the Ends of the Tigellum:**
- The tigellum has two ends:
- The micropolar end, which is rod-shaped and slightly bulged, known as the radical or embryonic root.
- The other end is located between the two cotyledons, referred to as the plumule or shoot tip.

6. **Conclusion:**
- Based on the analysis, the tigellum is best described as the embryonal axis. Therefore, the correct answer is option B: embryonal axis.

**Final Answer:**
Tigellum is the embryonal axis of the seed.

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