It occurs only in cells in the reproductive structures of organisms.
Meiosis only occurs in the reproductive cells, producing gametes with half of the genetic information as the parent cell.
An organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It has a double membrane, the inner layer being folded inward to form layers (cristae).
A embryo is the unborn child from when they were conceived to 10 weeks and fetus is the unborn child from 11 weeks till birth
For giving you understanding ; we need Free O2 but Oxygen is also available in H20 right why dont we use it !!
As the early atmosphere was reducing as there was no free oxygen but it was later produced by chemoautotrophic bacteria !! Living thing release O2 in atmosphere thus making it oxidising in nature and then life evolves !!
