Question

explain the dyad megaspore in short...​

Answer 1

The dyad gene is required for progression through female meiosis in Arabidopsis. ... The female gametophyte or embryo sac, is contained within the ovule and develops from a single cell, the megaspore which is formed by meiosis of the megaspore mother cell.....

Megaspores, also called macrospores, are a type of spore that is present in heterosporous plants. These plants have two spore types, megaspores and microspores. Generally speaking, the megaspore, or large spore, germinates into a female gametophyte, which produces egg cells. These are fertilized by sperm produced by the male gametophyte developing from the microspore. Heterosporous plants include the following:

1.    seed plants (gymnosperms and flowering plants)
2.    water ferns (Salviniales)
3.    spikemosses (Selaginellaceae)