Which of the following is a wrong statement

Options

A. Pit cavity is uniformly wide in a simple pit
B. The thick middle portion of middle lamellum crossing the borderd pits is called torus
C. The diameter of the pit chamber gradually decreases towards Lumen of the cell in simple pit.
D. Secondary wall is absent in meristematic cells.

Answer

To determine which statement is incorrect, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- The first statement claims that the pit cavity is uniformly wide in a simple pit.
- In a simple pit, the pit cavity is indeed uniform in width. This statement is **true**.

2. **Evaluate the Second Statement:**
- The second statement discusses the thick middle portion of the middle lamella when it crosses the bordered pits, referring to it as the torus.
- The torus is a thickened part of the middle lamella that can be observed in bordered pits. This statement is also **true**.

3. **Evaluate the Third Statement:**
- The third statement states that the diameter of the pit chamber gradually decreases towards the lumen of the cell in the simple pit.
- This statement is incorrect because, in a simple pit, the diameter of the pit chamber actually increases towards the lumen. Therefore, this statement is **false**.

4. **Evaluate the Fourth Statement:**
- The fourth statement asserts that the secondary wall is absent in meristematic cells.
- It is correct that meristematic cells primarily have a primary wall and do not have a secondary wall, making this statement **true**.

### Conclusion:
The incorrect statement among the options provided is the **third statement**, which states that the diameter of the pit chamber decreases towards the lumen of the cell in the simple pit.

### Final Answer:
The wrong statement is: **The diameter of the pit chamber gradually decreases towards the lumen of the cell in the simple pit.**

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