Which one is wrong

Options

A. Vegetative cell is larger than generative cell
B. Intine is made of cellulose and pectin
C. Pollen grains of some plants remain viable for months
D. Double fertilization is absent where pollen is shed in 2- celled stage.

Answer

To solve the question "Which one is wrong?" regarding pollen grains and their characteristics, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding the Cells in Pollen Grains:**
- Pollen grains consist of two types of cells: the vegetative cell and the generative cell.
- The vegetative cell is larger and contains abundant cytoplasm, while the generative cell is smaller and has less cytoplasm.

**Hint:** Remember the size difference and cytoplasmic content between vegetative and generative cells.

2. **Analyzing the Composition of the Pollen Grain Layers:**
- Pollen grains have two layers: the outer layer (exine) and the inner layer (intine).
- The outer layer (exine) is made of sporopollenin, while the inner layer (intine) is composed of cellulose and pectin.

**Hint:** Focus on the distinction between exine and intine and their respective compositions.

3. **Viability of Pollen Grains:**
- It is true that pollen grains of some plants can remain viable for months. This statement is correct.

**Hint:** Consider the longevity of pollen grains in various plant species.

4. **Double Fertilization and Pollen Stage:**
- The statement claims that double fertilization is absent when pollen is shed in the two-cell stage. However, in most angiosperms, pollen is indeed shed in the two-cell stage, and upon landing on the stigma, it can develop into a three-cell stage, leading to double fertilization.
- Therefore, the assertion that double fertilization is absent in this case is incorrect.

**Hint:** Recall the process of double fertilization and the significance of the two-cell stage in angiosperms.

### Conclusion:
Based on the analysis of each statement, the fourth statement is the one that is wrong. Therefore, the answer to the question "Which one is wrong?" is:

**Answer: The fourth statement is wrong.**