Select false statement -

Options

A. In leaves, the ground tissue consists of thin walled chloroplast containing cells which is called mesophyll
B. The stomatal aperture, guard cells and the surrounding subsidiary cells are together called stomatal apparatus
C. The root hairs are unicellular elongation of the epidermal cells.
D. The protophloem has bigger sieve tubes whereas metaphloem has narrow sieve tubes

Answer

To determine which statement is false, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The statement claims that the ground tissue in leaves consists of thin-walled chloroplast-containing cells called mesophyll.
- **Explanation:** Mesophyll cells are indeed responsible for photosynthesis and contain chloroplasts. This statement is true.

2. **Analyze the Second Statement:**
- The statement mentions that the stomatal aperture, guard cells, and surrounding subsidiary cells together are called the stomatal apparatus.
- **Explanation:** This is accurate as the stomatal apparatus includes guard cells and subsidiary cells, which regulate the opening and closing of the stomatal aperture for gas exchange. This statement is true.

3. **Analyze the Third Statement:**
- The statement describes that roots have unicellular elongation of epidermal cells.
- **Explanation:** This is correct because root hairs are extensions of epidermal cells that increase surface area for absorption. This statement is true.

4. **Analyze the Fourth Statement:**
- The statement asserts that protoxylem has bigger sieve tubes while metaphloem has narrower sieve tubes.
- **Explanation:** This is incorrect. Protoxylem actually has narrower sieve tubes, while metaphloem has wider sieve tubes. This statement is false.

### Conclusion:
The false statement is the fourth one: "protoxylem has bigger sieve tubes whereas metaphloem has narrower sieve tubes."

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