Embryo sac is surrounded by a wall of

Options

A. Specialized nucellar cells
B. Transfer cells
C. Membrane of megaspore
D. Membrane of egg.

Answer

**Step-by-Step Solution:**

1. **Understanding the Embryo Sac**: The embryo sac is a crucial structure in the female reproductive part of flowering plants. It contains the egg cell and is formed from the megaspore mother cell (MSMC).

2. **Formation of the Embryo Sac**: The megaspore mother cell undergoes meiosis. This process involves the division of the diploid megaspore mother cell (2n) to produce four haploid nuclei (n) through meiotic division.

3. **Mitosis of Daughter Nuclei**: The four haploid nuclei then undergo mitotic divisions. This means that each of the four nuclei divides without further reduction in chromosome number, resulting in a total of eight haploid nuclei.

4. **Lack of Cytokinesis**: At this stage, it is important to note that there is no cytokinesis occurring. Cytokinesis is the process where the cytoplasm divides to form separate cells. Instead, all eight nuclei remain within a single cell structure.

5. **Surrounding Wall of the Embryo Sac**: The wall that surrounds these eight nuclei is derived from the original megaspore cell wall. Therefore, the embryo sac is surrounded by the membrane of the megaspore.

6. **Conclusion**: The correct answer to the question "Embryo sac is surrounded by a wall of" is the "membrane of megaspore."

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