What is the term used to describe the formation of the embryo sac from a single megaspore?

Monosporic development

The correct answer is Option (2)- Monosporic development.

Monosporic development is the process of forming an embryo sac from a single megaspore. This is the most common type of embryo sac development in flowering plants.

In monosporic development, the megaspore mother cell undergoes meiosis and forms four megaspores. However, only one of these megaspores is functional and develops into the embryo sac. The other three megaspores degenerate.

The functional megaspore undergoes three rounds of mitosis to form the mature embryo sac. The mature embryo sac contains seven cells and eight nuclei. The egg cell is fertilized by a sperm cell to produce a zygote.

The cells of the embryo sac are:

• Two synergids: These cells are located near the micropyle of the embryo sac and help to guide the sperm cells to the egg cell.
• An egg cell: This is the female gamete that can be fertilized by a sperm cell to produce a zygote.
• Three antipodals: These cells are located at the opposite end of the embryo sac from the egg cell and do not play a direct role in fertilization.
• One central cell

Polymeric development, bisporic development, and multisporic development are all types of embryo sac development in which more than one megaspore is involved in the formation of the embryo sac.