Question

Antrum is the cavity of

• A. Blastula
• B. Gastrula
• C. Neurala
• D. Graafian follicle

Answer 1

The correct option is D

Graafian follicle

The antrum is a fluid-filled space (fluid = liquor folliculi) that develops among the follicle cells; it starts as multiple small spaces that eventually coalesce into a single large antrum. Oogenesis is initiated during the embryonic development stage when a couple of million gamete mother cells (oogonia) are formed within each foetal ovary These cells start division and enter into prophase-I of the meiotic division and get temporarily arrested at that stage, at which they are known as primary oocytes. Each primary oocyte later, gets surrounded by a layer of granulosa cells and are called the primary follicles. The primary follicles get surrounded by more layers of granulosa cells and a new theca, and are called secondary follicles. The secondary follicle soon transforms into a tertiary follicle which is characterised by a fluid-filled cavity called antrum. One of these tertiary follicles that undergoes further maturation is known as the Graafian follicle.