Through which cell of the embryo sac, does the pollen tube enter the embryo sac

Options

A. egg cell
B. persistant synergid
C. degenerated synergid
D. central cell

Explanation

To answer the question "Through which cell of the embryo sac does the pollen tube enter the embryo sac?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure of the Embryo Sac**:
- The embryo sac, also known as the female gametophyte, consists of several cells: one egg cell, two synergid cells, and one central cell. The synergid cells are located laterally to the egg cell.

2. **Role of the Pollen Tube**:
- When pollen grains land on the stigma of a flower, they germinate and form a pollen tube. This tube grows down through the style toward the ovule, carrying male gametes.

3. **Entry Point of the Pollen Tube**:
- The pollen tube enters the embryo sac through an opening called the micropyle, which is located at the micropilar end of the embryo sac.

4. **Cells Involved in the Entry**:
- The pollen tube can penetrate the embryo sac through the synergid cells. Specifically, it can enter directly through one of the synergids.

5. **Degeneration of Synergid Cells**:
- Upon the arrival of the pollen tube, the synergid cells undergo degeneration. This degeneration facilitates the entry of the pollen tube into the embryo sac.

6. **Conclusion**:
- Based on the above points, the correct answer to the question is that the pollen tube enters the embryo sac through the **degenerated synergid**.

### Final Answer:
The pollen tube enters the embryo sac through the **degenerated synergid**.

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