The Full Wiki

More info on Oogonia

Oogonia: Wikis

Advertisements

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

(Redirected to Oogonium article)

From Wikipedia, the free encyclopedia

Oogonium
Gray's subject #3 38
MeSH Oogonia

An oogonium (plural oogonia) is an immature ovum. It is a female gametogonium. They are formed in large numbers by mitosis early in fetal life from primordial germ cells, which are present in the fetus between weeks 4 and 8.

Oogonia are present in the fetus between weeks 5 and 30.

Oogonia are also the female reproductive structures in certain thallophytes, and are usually rounded cells or sacs containing one or more oospheres.

Contents

Further development

Once the primordial germ cells have gotten to the ovary, they develop into oogonia. During week 6 of development, oogonia migrate from the yolk sac to the genital ridge ( site of the future gonads-ovaries in this case) located on the posterior abdominal wall. Oogonia develop by mitosis. However, some of them become primary oocytes, which begin meiosis which is halted in prophase I. When they have entered Prophase I of meiosis they become primary oocytes; it is important to note that this process is complete before birth, in contrast to spermatogenesis. Primary oocytes are present from week 10 until menopause at ~53 years

Oogamy

Oogamy may be spelt oögamy with a diaraesis (or umlaut). The link with other articles may depend on this symbol.

Oogonia

Advertisements

Algae

This term is used in phycology (the study of algae) to refer to the union of the male (motile or non-motile) with the female gamete.[1 ]The female oogonium is usually enlarged and develops a single ovum. The male (antheridium) usually produces many cells with flagella except in the Rhodophyta which have no flagella. [2]

Fungi

Oogonia also occur in the fungi.[3]

References

  1. ^ Stegenga, H. Bolton, J.J. and Anderson, R.J. 1997. Seaweeds of the South African West Coast. Bolus Herbarium, University of Cape Tow. ISBN 0 7992 1793 X
  2. ^ Fritsch, F.E. 1965. The Structure and Reproduction of the Algae. Vol. 1 Cambridge University Press
  3. ^ Smyth, G.M. 1955. Cryptogamic Botany. vol. 1. McGraw-Hill Book Company

External links


Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message