QS Study

The ovaries are a pair of female reproductive glands which are situated in the lesser pelvis one on each side of the uterus and attached to the posterior layer of the broad ligament below and behind the corresponding uterine tube. The ovary is within the ovarian fossa, a space that is bound by the external iliac vessels, obliterated umbilical artery, and the ureter.

Structure

The ovary is covered by a single layer of cuboidal cells, known as germinal epithelium. Beneath it, dense connective tissue tunica albuginea is present. Below this, the ovarian substance is divided into the inner medulla and outer cortex.

Medulla:

It consists of loose connective tissue, smooth muscles, blood vessels, lymphatics, and nerves.

Cortex:

The cortex contains a stroma cell which consists of different structures during different periods of life. At birth, the cortex contains about 2 lacs primary follicles which reduced to 40 thousand at puberty. Each follicle is covered by a single layer of the follicular cell (flattened epithelium).

From the beginning of puberty, some follicles undergo maturation in each menstrual cycle. One of them fully matures and ruptures, discharging a secondary oocyte in each month. Rest of the follicles become atretic and are converted into interstitial cells. A mature follicle is known as a graffian follicle.

Fig: Structure of the Ovary

The structures found in graffians follicle are –

  1. Oocyte,
  2. Zona pellucida,
  3. Antrum follicle.
  4. Membrane granulosa,
  5. Cumulus oophorus,
  6. Theca interna,
  7. Theca externa.

After menopause, the cortex becomes atretic, It contains interstitial cells and corpus albicans.

Development

The ovaries develop from a condensed region in the embryonic gonadal ridge just medial to the mesonephros, in a manner similar to the testes. The different parts of ovary develop from the following sources –

(i) Oocyte: From primordial germ cell,

(ii) Primordial follicle: From cells of sex cords, which come from coelomic epithelium,

(iii) Interstitial cells: From mesenchyme,

Function

The ovaries have three functions. First, they shelter and protect the eggs a female is born with until they are ready for use. Second, ovaries produce female reproductive hormones called estrogen and progesterone, and some lesser hormones called relaxin and inhibin. Third, ovaries release one egg, or sometimes more, each menstrual cycle.

  • Secrete ova which are the female garnets,
  • Secrete female sex hormones, entrogen, and progesterone.
Related Study: