Which is not true

Options

A. Pollen grains are released from anthers at 2-celled stage
B. Sporogenous cell directly behaves as megaspore mother cell
C. Megaspore divides twice to form an 8-nucleate embryo sac
D. Egg and synergids always lie near micropylar end.

Answer

To determine which statement is not true, we will analyze the statements provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Pollen Grain Development**:
- Pollen grains are released from the anthers at a two-cell stage, which consists of a vegetative cell and a generative cell.
- This process occurs in approximately 60% of angiosperms.
- **Conclusion**: This statement is true.

2. **Sporogenous Cell Behavior**:
- The sporogenous cell behaves as a megaspore mother cell.
- It divides to form megaspores, which will eventually develop into pollen grains.
- **Conclusion**: This statement is also true.

3. **Megaspore Division**:
- A megaspore divides mitotically to form four haploid structures, but only one of these remains functional while the other three degenerate.
- The functional megaspore then divides three times to form an 8-nucleate embryo sac.
- **Conclusion**: This statement is incorrect because it suggests that the megaspore divides to form an 8-nucleate structure directly, which is misleading.

4. **Position of Eggs and Synergids**:
- Eggs and synergids are located near the micropyle end of the embryo sac.
- This is a correct statement as the egg cell and synergids are positioned towards the micropyle.
- **Conclusion**: This statement is true.

### Final Conclusion:
- The statement that is not true is the one regarding the megaspore dividing to form an 8-nucleate structure directly. Therefore, the correct option indicating the incorrect statement is option number 3.