Megagametes

Megagametes are large, non-motile gametes produced by certain organisms, particularly in the plant kingdom. They are characterized by their size, which can be significantly larger than the smaller, motile microgametes also produced by the same organism. This size disparity is a key feature that distinguishes megagametes from microgametes. Megagametes are typically produced by the female parent and are involved in sexual reproduction. In plants, megagametes develop within the ovule, a structure found in the ovary of the flower. The megagamete undergoes meiosis to produce a haploid nucleus, which then develops into the female gametophyte. This gametophyte contains the egg cell, which is fertilized by the sperm cell carried by the pollen grain, leading to the formation of the embryo. Megagametes are not found in all organisms; their presence is more common in seed plants and some algae.