Megagametogenesis

Definition

Megagametogenesis is the process by which the female gametophyte, or embryo sac, develops from the megaspore in seed plants. This stage follows megasporogenesis and involves cell division and differentiation to form the mature gametophyte.

5 Must Know Facts For Your Next Test

1. Megagametogenesis occurs within the ovule of flowering plants.
2. The process begins with a single functional megaspore produced by meiosis of a megasporocyte.
3. The megaspore undergoes three rounds of mitotic division to form an eight-nucleate, seven-celled structure.
4. Important cells formed during this process include the egg cell, synergids, antipodal cells, and central cell.
5. Megagametogenesis is crucial for sexual reproduction as it leads to the formation of the female gamete that will participate in fertilization.

Review Questions

• What is the starting point of megagametogenesis?
• How many nuclei are present in the mature female gametophyte after megagametogenesis?
• Name at least two types of cells that are formed during megagametogenesis.

Related terms

Megasporogenesis: The process involving meiosis that results in the formation of four megaspores from a megasporocyte.

Microgametogenesis: The development of male gametophytes (pollen grains) from microspores in seed plants.

Embryo Sac: The mature female gametophyte within the ovule where fertilization occurs.