For the formation of embryo sac the _________undergo__________meiotic and _______division.

Answer

**Step-by-Step Solution:**

1. **Identify the Structure Involved**: The formation of the embryo sac involves the megaspore mother cell (MMC), which is crucial in the development of the female gametophyte.

2. **Understand the Process**: The megaspore mother cell undergoes a series of divisions to form the embryo sac.

3. **Division Types**:
- The megaspore mother cell first undergoes **one meiotic division**. This division is essential as it reduces the chromosome number by half, creating haploid cells.
- Following the meiotic division, the remaining cell undergoes **three mitotic divisions**. These mitotic divisions are responsible for the formation of the eight nuclei that will eventually organize into the embryo sac.

4. **Final Answer Construction**: Based on the above points, we can fill in the blanks in the question:
- For the formation of embryo sac, the **megaspore mother cell** undergoes **one meiotic** and **three mitotic** divisions.

**Final Answer**: For the formation of embryo sac, the **megaspore mother cell** undergoes **one meiotic** and **three mitotic** divisions.

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