Question

1) In which organ the embryo nests and develops until its birth.
a) Of the organ mentioned in the previous paragraph, say its portions.
b) Briefly explain the female sexual cycle.

Answer 1

As far as human beings are considered, it is the uterus that the embryo gets attached to and grows until birth. The different parts of the uterus are the body, fundus, isthmus, cervix, cervical canal, perimetrium, myometrium, and endometrium.

The female sexual or reproductive cycle has broadly 2 parts such as the ovarian cycle and the endometrial cycle. The ovarian cycle is divided into 3 phases such as follicular, ovulation, and luteal phase. In the follicular phase, a mature egg is formed, while in the ovulation phase mature oocyte is released following the rupture of the follicle. As far as the luteal phase is considered, mature oocyte fails to meet sperm and ultimately a series of events happen to lead to the expulsion of oocyte and other menstrual products to the outside of the body. The endometrial cycle has 4 parts such as proliferative, secretory, ischemic, and menstrual. In the proliferative phase, there is an enlargement of endometrial glands. While in the secretory phase, there is the active participation of progesterone by LH which helps prepare endometrium ready for receiving a fertilized ovum. Ischemic phase happens when there is no reception of fertilised egg and endometrial shedding begins. The final phase is the menstrual phase where the entire shredded product of uterus gets ejected from the uterus through the outlet called cervix.