What is oogenessis?

Answer 1

This is the process by which eggs (ova) are made.

It begins with the primordial germ cells (also called oogonium) which are diploid (have the full set of paired chromosomes). They divide by mitosis to produce primary oocytes. Then a primary oocyte undergoes a first meiotic division creating a secondary oocyte and a first polar body (which dies). Then after the second meiotic division of the secondary oocyte, an ootid (now haploid - i.e. has full set of unpaired chromosomes) results, along with a second polar body (which dies just like the first one). The ootid then develops into an ovum (egg).