The figure below shows a section of the human ovary. Select the option which gives the correct identification of labellings (A to D).
The ovary is the primary female reproductive organ that produces the ovum, secretes hormones and releases eggs for the fertilisation process.
Primary follicles are formed when a granulosa layer surrounds the primary oocyte (they are arrested during fetal development).
Primary follicles when they get surrounded by more layers of granulosa cells and new theca, they transform into secondary follicles. Secondary follicles on further development transform into a tertiary follicle which is characterized by the fluid-filled cavity called the antrum.
The tertiary follicle grows further into the Graafian follicle with a large follicular cavity or antrum that is filled by a liquid called a liquor folliculi.
Corpus luteum is a yellow, hormone-secreting mass of cells that forms in an ovary at the site of follicle. Corpus luteum acts like an endocrine gland as it produces majorly progesterone and a small amount of estrogen. If fertilisation does not occur, corpus luteum becomes inactive and degenerates into a structure called corpus albicans.