Study this page on the production
of ova. When you are ready go to the page of problems
on ova production. Make sure that you can recognise the different
When you have completed both
the work on this page (including the problems on ova production) and on
the sexual cycle try the oestrus
The production of ova involves
cell division. Make sure that you know the difference between mitosis
The diagram below shows the
stages in the production of ova inside an ovary.
Under the influence of hormones
one or more (depending on the type of animal) of the primary follicles
starts to develop. The photographs below show the stages of development.
follicles. Each of these is composed of a developing egg cell
(primary oocyte) surrounded by a layer of follicle cells.
ovarian follicles. The follicle cells divide and a fluid filled
cavity is formed. The egg cell has become a secondary oocyte.
ovarian follicle (a Graafian
follicle in older texts). The follicle is now ready for ovulation
when the secondary oocyte bursts through the ovary wall.
luteum. After ovulation the follicle
cells form this glandular tissue that secretes progesterone.