To form four fully developed Polygonum type of embryo sacs in angiosperms total number of meiosis and mitosis divisions generations required are

Options

A. 4,12
B. 1,3
C. 4,4
D. 1,12

Answer

To determine the total number of meiosis and mitosis divisions required to form four fully developed Polygonum type embryo sacs in angiosperms, we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding the Polygonum Type Embryo Sac**:
- The Polygonum type embryo sac is a structure that typically contains 7 cells and 8 nuclei. This structure is formed through a series of meiotic and mitotic divisions.

2. **Meiosis in Embryo Sac Formation**:
- In angiosperms, the formation of the embryo sac begins with a megaspore mother cell (megasporangium).
- This megaspore mother cell undergoes **1 meiosis** to produce **4 megaspores**. However, typically only **1 megaspore** survives to develop into the embryo sac, while the other three degenerate.

3. **Mitosis in Embryo Sac Development**:
- After the formation of the surviving megaspore, it undergoes **3 mitotic divisions**.
- These mitotic divisions lead to the development of the 7-celled, 8-nucleated structure characteristic of the Polygonum type embryo sac.

4. **Calculating for Four Embryo Sacs**:
- Since we need to form **4 fully developed embryo sacs**, we need to multiply the number of meiotic and mitotic divisions by 4.
- **Meiosis**: For 4 embryo sacs, we need **4 meiosis** (1 meiosis per embryo sac).
- **Mitosis**: For 4 embryo sacs, we need **12 mitotic divisions** (3 mitosis per embryo sac × 4 embryo sacs = 12 mitosis).

5. **Final Count**:
- Therefore, the total number of divisions required to form four fully developed Polygonum type embryo sacs is:
- **4 meiosis**
- **12 mitosis**

### Conclusion:
The total number of meiosis and mitosis divisions required to form four fully developed Polygonum type embryo sacs in angiosperms is **4 meiosis and 12 mitosis**.