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 follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure**: The Polygonum type embryo sac in angiosperms is characterized by having 7 cells and 8 nuclei.

2. **Identifying the Initial Cell**: The development of the embryo sac starts from a single Megaspore Mother Cell (MMC).

3. **Meiosis Division**:
- The Megaspore Mother Cell undergoes **one meiosis** to produce four haploid megaspores.
- Out of these four megaspores, typically only one survives to develop into the embryo sac, while the others degenerate.

4. **Mitosis Divisions**:
- After meiosis, the surviving megaspore undergoes **three mitotic divisions**.
- Each mitotic division results in an increase in the number of nuclei, leading to the formation of the 7-celled, 8-nucleated structure characteristic of the Polygonum type embryo sac.

5. **Total Calculations for Four Embryo Sacs**:
- Since we need to form **four embryo sacs**, we will multiply the number of meiosis and mitosis divisions accordingly:
- **Meiosis**: For four embryo sacs, we will need **4 meiosis divisions** (1 meiosis per embryo sac).
- **Mitosis**: Each embryo sac requires **3 mitosis divisions**, so for four embryo sacs, we will need **4 x 3 = 12 mitosis divisions**.

6. **Final Count**:
- Therefore, to form four fully developed Polygonum type embryo sacs, we require:
- **Total Meiosis**: 4
- **Total Mitosis**: 12

### Summary:
To form four fully developed Polygonum type embryo sacs in angiosperms, the total number of divisions required are:
- **Meiosis**: 4
- **Mitosis**: 12