Functional megaspre in an angiosperm develops into

Options

A. ovule
B. endosperm and cotyledons
C. embryo sac
D. embryo

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what the functional megaspore in an angiosperm develops into.

2. **Definition of Megaspore**: In angiosperms (flowering plants), the megaspore is a type of spore that is involved in the formation of the female gametophyte.

3. **Process of Megasporogenesis**: The functional megaspore is produced through a process called megasporogenesis, which occurs in the ovule.

4. **Formation of Megaspores**: During megasporogenesis, a diploid megasporangium undergoes meiosis to produce four haploid megaspores. Out of these four, typically only one megaspore remains functional while the other three degenerate.

5. **Development of the Functional Megaspore**: The functional megaspore undergoes mitotic divisions. Initially, it divides to form two nuclei, then four nuclei, and finally eight nuclei without cytokinesis occurring between these divisions.

6. **Formation of the Embryo Sac**: The eight nuclei are then arranged in a specific pattern and are surrounded by a cytoplasmic membrane, forming a structure known as the embryo sac. This embryo sac is also referred to as the female gametophyte.

7. **Conclusion**: Therefore, the functional megaspore in an angiosperm develops into the embryo sac.

**Final Answer**: The functional megaspore in an angiosperm develops into the embryo sac.

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