Cells which surround the oocyte in Graafian follicle are called
**Core Concept**
The question is testing the understanding of ovarian follicular structure and the specific cell types involved in the Graafian follicle. The Graafian follicle is a mature ovarian follicle that is ready to release an oocyte during ovulation.
**Why the Correct Answer is Right**
The cells that surround the oocyte in the Graafian follicle are called granulosa cells. These cells play a crucial role in the development and maturation of the oocyte. They produce hormones such as estrogen and inhibit, which regulate the growth of the follicle and prepare the oocyte for ovulation. The granulosa cells also provide nourishment and support to the oocyte, helping it to mature and develop properly.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify the type of cell that surrounds the oocyte in the Graafian follicle. While other cells such as theca cells and cumulus cells are also present in the follicle, they are not the primary cells that surround the oocyte.
* **Option B:** This option is incorrect because it is a type of cell that is present in the follicle but is not the primary cell that surrounds the oocyte.
* **Option C:** This option is incorrect because it is a type of cell that is not typically associated with the Graafian follicle.
**Clinical Pearl / High-Yield Fact**
It's worth noting that the granulosa cells play a crucial role in the development of the corpus luteum after ovulation, which is essential for maintaining pregnancy.
**Correct Answer:** D. **Granulosa cells**