Antrum is the cavity of
- A. Morula
- B. Graafian follicle
- C. Blastula
- D. Pineal
Answer: B. Graafian follicle
Graafian follicle is marked by the formation of a fluid-filled cavity adjacent to the oocyte, called as the antrum. Antrum refers to a fluid-filled cavity that develops within a mature ovarian follicle.