Question

1. What would happen if the follicle could not produce Theca cells?
   1. Ovulation would not occur.
   2. Granulosa cells would not be able to produce androstenedione.
   3. FSH would no longer be able to signal to granulosa cells.
   4. All of the above.  

Answer 1

Answer:

Option B: Granulosa cells would not be able to produce androstenedione

Explanation: Oogenesis is the process of formation of the female gametes that is ovum in the ovary of the females. It is a very complicated process and therefore gets initiated during the embryogenesis itself.

The primordial germ cell is the oogonia which undergo a number of mitotic and meiotic divisions to give rise to primary, secondary and the tertiary oocyte. Tertiary oocyte is also called as the mature Graffian follicle and it contain the secondary oocyte within it.

Structure of a Graffian follicle/Tertiary follicle:

The secondary oocyte which is present inside the mature Graffian follicle remains surrounded by a membranous layer made of cells called as the Zona pellucida. Zona pellucida plays a very important role in the fertilization or the process of amphimixis as the spermatozoa which enters the female reproductive tract gets to contact the cellular receptor located over the surface of zona pellucida only.

The zona pellucida layer remains surrounded by another layer of the follicular cells which are called as the Granulosa cells. The major function of the granulosa cell is to release and secrete the hormone estrogen upon attaining the follicular growth. Thus granulosa cells thus acts as an endocrine gland. It is to be noted that the entire female reproductive hormone are derived from the primary androgen; testosterone which is a cholesterol derivative.

The follicular granulosa cells remains further surrounded by a layer of cells namely the theca interna and the theca externa. The word theca means the cover and they are made of connective tissues and the blood vessels which supplies the nutrients to the developing follicle. The theca layers of the cells are associated with the endocrine functioning of the granulosa cells. That is they facilitate the granulosa cells to synthesize and form the hormone estrogen which plays an important role in maintaining and regulating the secondary sexual development of the females by leading and forming the receptors for the hormone androstenedione.

The hormone then is passed on to the granulosa cells which stimulates them for the formation of estrogens since as discussed before, the precursor for all the female reproductive hormones is the testosterone.

Thus in case the Theca cells of the follicle cell gets impaired, the endocrine function of the granulose cells underlying them too will be impaired.