Structure of Ovary

The labelled diagram of ovary shows its detailed structure. Women have two ovaries, one on each side of the uterus in a spot called the ovarian fossa. One side is linked to the fallopian tube by the infundibulopelvic ligament, and the other side connects to the uterus by ovarian ligaments. Each ovary is attached to the uterus by the mesovarium and ovarian ligament.

Each ovary is divided into two major parts –

• Medulla
• Cortex

Medulla

The ovarian medulla is also known as the zona vasculosa of Waldeyer. It is the innermost layer of the ovary and made of loose connective tissues. These tissues contain the blood vessels, lymphatic vessels, and nerves. It is located in the center of the ovary or in particular deep to the ovarian cortex. The medulla forms the tissue of the hilum. Hilum is the attachment point for the ovarian ligament, through which blood vessels enter. The medulla does not contain any ovarian follicles.

Cortex

The ovarian cortex is the outer layer of the ovary. It made up of the connective tissues. It contains ovarian follicles. The ovarian cortex is the peripheral zone around the medulla of the ovary and the ovarian cortex contains the follicles. It includes the cumulus oophorus, membrana granulosa,primary oocyte, corona radiata and zona pellucida.

Ovarian Follicles

Within the cortex, the outer layer comprises germinal epithelium originating from the germinal ridges. This epithelium gives rise to primordial eggs, which migrate to the inner cortex. Surrounded by granulosa cells, the primordial egg cells form primordial follicles, which develop into tertiary vesicular follicles containing an antrum. The mature follicle, known as the Graafian follicle, releases the ovum upon rupture.

During fetal development, the ovary initially contains approximately 6 million primordial follicles, but by birth, only around 1 million remain, with the rest degenerating over time. During each menstrual cycle, only one egg is released from each ovary, while the others undergo degeneration. After ovulation, the remnants of ovarian follicles form the corpus luteum, which eventually regresses to become corpus albicans.

The diagram of ovary of a human shows the anatomical structure responsible for producing and releasing eggs. An ovary is a small and oval-shaped reproductive organ of females. It produces ova and hormones that regulate fertility, pregnancy, and the menstrual cycle. Ovaries are located in the lower left and right quadrants of the abdomen. The diagram of ovary class 12 is an important topic of the biology syllabus.

The labeled diagram of ovary is given below: