Hard bast (Bundle cap ) occurs in

Options

A. (a) Sunflower stem
B. (b) Wheat stem
C. (c) Sunflower root
D. (d) Both (a) and (b)

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Hard Bast" (Bundle Cap):**
- The term "hard bast" refers to a specific type of tissue known as the bundle cap, which is composed of sclerenchymal tissue.
- This tissue is located between the cortex and the pith in certain plant structures.

2. **Identifying the Function:**
- The primary function of the bundle cap is to provide additional mechanical support to the plant.

3. **Locating the Bundle Cap in Plant Structures:**
- The bundle cap is typically found in the transverse section of dicot stems.
- In a transverse section, it can be identified as a patch of sclerenchymal tissue situated between the cortex and the pith.

4. **Analyzing the Options Given:**
- The options provided are:
a) Sunflower stem (a dicot)
b) Wheat stem (a monocot)
c) Sunflower root
d) Both a and b
- We need to determine which of these options contain the bundle cap.

5. **Evaluating Each Option:**
- **Option a (Sunflower stem):** As a dicot, the sunflower stem does contain the bundle cap. This is a correct option.
- **Option b (Wheat stem):** Wheat is a monocot, and monocots do not have a bundle cap. This option is incorrect.
- **Option c (Sunflower root):** The bundle cap is absent in the roots, making this option incorrect.
- **Option d (Both a and b):** Since option b is incorrect, this option is also incorrect.

6. **Conclusion:**
- The only correct option that contains the hard bast (bundle cap) is **option a: Sunflower stem**.

**Final Answer:** The hard bast (bundle cap) occurs in the sunflower stem (option a).

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