Ovary


Ovary
"Ovaria" redirects here. This is also a proposed section and a synonym of Solanum.
Ovary
Gray589.png
Blood supply of the human female reproductive organs. The left ovary is visible above the label "ovarian arteries".
Latin ovarium
Gray's subject #266 1254
Artery ovarian artery, uterine artery
Vein ovarian vein
Nerve ovarian plexus
Lymph Paraaortic lymph node
MeSH Ovary
Dorlands/Elsevier Ovary

The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.

Contents

Human anatomy

Ovaries are oval shaped. The ovary (for a given side) is located in the lateral wall of the pelvis in a region called the ovarian fossa. The fossa usually lies beneath the external iliac artery and in front of the ureter and the internal iliac artery.

The ovaries aren't attached to the fallopian tubes but to the outer layer of the uterus via the ovarian ligaments. Usually each ovary takes turns releasing eggs every month; however, if there was a case where one ovary was absent or dysfunctional then the other ovary would continue providing eggs to be released.

Hormones

Ovaries secrete both estrogen and progesterone. Estrogen is responsible for the appearance of secondary sex characteristics of anatomically female people at puberty and for the maturation and maintenance of the reproductive organs in their mature functional state. Progesterone functions with estrogen by promoting menstrual cycle cyclic changes in the endometrium.

Ligaments

In the human the paired ovaries lie within the pelvic cavity, on either side of the uterus, to which they are attached via a fibrous cord called the ovarian ligament. The ovaries are uncovered in the peritoneal cavity but are tethered to the body wall via the suspensory ligament of the ovary. The part of the broad ligament of the uterus that covers the ovary is known as the mesovarium. Thus, the ovary is the only organ in the human body which is totally invaginated into the peritonium, making it the only interperitoneal organ (not to be confused with intraperitoneal).

Uterus

Extremities

There are two extremities to the ovary:

  • The end to which the uterine tube attaches is called the tubal extremity.
  • The other extremity is called the uterine extremity. It points downward, and it is attached to the uterus via the ovarian ligament.

Histology

Cell types

  • Follicular cells flat epithelial cells that originate from surface epithelium covering the ovary
  • granulosa cells - surrounding follicular cells have changed from flat to cuboidal and proliferated to produce a stratified epithelium
  • Gametes[1]
Section of the ovary of a newly born child. Germinal epithelium is seen at top. Primitive ova are seen in their cell-nests. The Genital cord or genital ridge is still discernible in this young child. A blood vessel and an ovarian follicle is also seen

In other animals

Ovaries of some kind are found in the female reproductive system of many animals that employ sexual reproduction, including invertebrates. However, they develop in a very different way in most invertebrates than they do in vertebrates, and are not truly homologous.[2]

Many of the features found in human ovaries are common to all vertebrates, including the presence of follicular cells, tunica albuginea, and so on. However, many species produce a far greater number of eggs during their lifetime than do humans, so that, in fish and amphibians, there may be hundreds, or even millions of fertile eggs present in the ovary at any given time. In these species, fresh eggs may be developing from the germinal epithelium throughout life. Corpora lutea are found only in mammals, and in some elasmobranch fish; in other species, the remnants of the follicle are quickly resorbed by the ovary. In birds, reptiles, and monotremes, the egg is relatively large, filling the follicle, and distorting the shape of the ovary at maturity.[2]

Amphibians and reptiles have no ovarian medulla; the central part of the ovary is a hollow, lymph-filled space. The ovary of teleosts is also often hollow, but in this case, the eggs are shed into the cavity, which opens into the oviduct.[2]

Although most normal female vertebrates have two ovaries, this is not the case in all species. In birds and platypuses, the right ovary never matures, so that only the left is functional. In some elasmobranchs, the reverse is true, with only the right ovary fully developing. In the primitive jawless fish, and some teleosts, there is only one ovary, formed by the fusion of the paired organs in the embryo.[2]

Cryopreservation

Cryopreservation of ovarian tissue, often called Ovarian Tissue Cryopreservation, is of interest to women who want to preserve their reproductive function beyond the natural limit, or whose reproductive potential is threatened by cancer therapy,[3] for example in hematologic malignancies or breast cancer.[4] The procedure is to take a part of the ovary and carry out slow freezing before storing it in liquid nitrogen whilst therapy is undertaken. Tissue can then be thawed and implanted near the fallopian, either orthotopic (on the natural location) or heterotopic (on the abdominal wall),[4], where it starts to produce new eggs, allowing normal conception to take place. [5] A study of 60 procedures concluded that ovarian tissue harvesting appears to be safe.[4] The ovarian tissue may also be transplanted into mice that are immunocompromised (SCID mice) to avoid graft rejection, and tissue can be harvested later when mature follicles have developed.[6]

References

  1. ^ Langman's Medical Embryology, Lippincott Williams & Wilkins, 10th ed, 2006
  2. ^ a b c d Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 383–385. ISBN 0-03-910284-X. 
  3. ^ Isachenko V, Lapidus I, Isachenko E, et al. (2009). "Human ovarian tissue vitrification versus conventional freezing: morphological, endocrinological, and molecular biological evaluation.". Reproduction 138 (2): 319–27. doi:10.1530/REP-09-0039. PMID 19439559. 
  4. ^ a b c Oktay K, Oktem O (November 2008). "Ovarian cryopreservation and transplantation for fertility preservation for medical indications: report of an ongoing experience". Fertil. Steril. 93 (3): 762–8. doi:10.1016/j.fertnstert.2008.10.006. PMID 19013568. 
  5. ^ Livebirth after orthotopic transplantation of cryopreserved ovarian tissue The Lancet, Sep 24, 2004
  6. ^ Lan C, Xiao W, Xiao-Hui D, Chun-Yan H, Hong-Ling Y (December 2008). "Tissue culture before transplantation of frozen-thawed human fetal ovarian tissue into immunodeficient mice". Fertil. Steril. 93 (3): 913–9. doi:10.1016/j.fertnstert.2008.10.020. PMID 19108826. 

External links

  • [1] From the American Medical Association
  • [2] Merck Online Medical Library: Female Reproductive System

See also


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Look at other dictionaries:

  • ovary — (n.) 1650s, from Mod.L. ovarium ovary (16c.), from M.L. ovaria the ovary of a bird (13c.), from L. ovum egg, from PIE *owyo /*oyyo egg (see EGG (Cf. egg) (n.)). In classical Latin, ovarius meant egg keeper …   Etymology dictionary

  • Ovary — O va*ry ([=o] v[.a]*r[y^]), n.; pl. {Ovaries} ([=o] v[.a]*r[i^]z). [NL. ovarium, fr. L. ovum egg: cf. F. ovaire. See {Oval}.] 1. (Bot.) That part of the pistil which contains the seed, and in most flowering plants develops into the fruit. See… …   The Collaborative International Dictionary of English

  • ovary — ovary. См. завязь. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • ovary — ovary. См. яичник. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Óváry — (spr. ōwāri), Leopold, Ritter von, ungar. Historiker, geb. 31. Dez. 1833 in Veszprim, nahm 1848–49 am ungarischen und 1860 am italienischen Freiheitskampf teil und wurde 1867 in das ungarische Landesarchiv berufen, das er gegenwärtig als… …   Meyers Großes Konversations-Lexikon

  • ovary — ► NOUN (pl. ovaries) 1) a female reproductive organ in which ova or eggs are produced. 2) Botany the base of the carpel of a flower, containing one or more ovules. ORIGIN Latin ovarium, from ovum egg …   English terms dictionary

  • ovary — [ō′və rē] n. pl. ovaries [ModL ovarium < L ovum,EGG1] 1. Anat. Zool. a female reproductive gland producing eggs and, in vertebrates, sex hormones 2. Bot. the enlarged, hollow part of the pistil or gynoecium, containing ovules: see PISTIL… …   English World dictionary

  • ovary — Female reproductive organ, producing ova [Butler, T.H.]. In free living copepod unpaired, parasitic copepod paired, expanded section of female reproductive system in which eggs are produced. Located dorsally, above midgut, near border of head and …   Crustacea glossary

  • ovary — /oh veuh ree/, n., pl. ovaries. 1. Anat., Zool. the female gonad or reproductive gland, in which the ova and the hormones that regulate female secondary sex characteristics develop. 2. Bot. the enlarged lower part of the pistil in angiospermous… …   Universalium

  • Ovary — The female gonad, the ovary is one of a pair of reproductive glands in women. They are located in the pelvis, one on each side of the uterus. Each ovary is about the size and shape of an almond. The ovaries produce eggs (ova) and female hormones …   Medical dictionary


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