Question

The main function of the fimbriae of the fallopian tube in females is to
A. Release ovum from the Graafian follicle
B. Make necessary changes in the endometrium for implantation
C. Help in the development of corpus luteum
D. Help in the collection of the ovum after ovulation

Answer 1

Small cellular projections are usually present on the apical surfaces of the linings of the internal hollow organs. These projects assist in the movement of secretions or cells.

Complete answer:
We will first learn the events related to the oogenesis, ovulation, and regulatory hormones.
As we know that ovaries are the paired structures and serve as the site for the formation of female gametes in humans. The process of the formation of a female gamete is called oogenesis and starts with the onset of puberty in a follicle of an ovary. A mature follicle is called Graafian follicle that as a secondary oocyte stalled in the metaphase II of the meiosis II.
Let’s discuss the events that occur during the ovulation and the associated hormones. The process of oogenesis and ovulation is regulated by the gonadotropins (follicle-stimulating hormone and luteinizing hormone) secreted by the anterior pituitary. The follicle-stimulating hormone (FSH) predominates during the follicular phase of the ovary and triggers the development of follicles. The developing follicle releases an increasing amount of estrogen, which in turn, stimulates the hypothalamus to release an increased amount of GnRH (gonadotropin-releasing hormone, that triggers the release of gonadotropins from the anterior pituitary). It results in a surge of FSH and LH. The increased levels of luteinizing hormone (LH) trigger the ovulation, the release of the secondary oocyte from the Graafian follicle.
Now, since the egg is being formed in the ovaries, the uterus should be prepared for the possible implantation. Therefore, the follicular phase of the ovary coincides with the menstruation and proliferation phase. During the proliferation phase, estrogen released from the developing follicle triggers the thickening of the endometrium of the uterus. The endometrium becomes more vascularized to facilitate the implantation of the embryo if fertilization occurs.
One should know that progesterone and estrogen are required to prevent menses if pregnancy occurs. Since placenta formation takes time, a temporary endocrine gland is formed to ensure the continuous secretion of these hormones. After the release of the secondary oocyte from the Graafian follicle, LH triggers the transformation of the ruptured follicle into the corpus luteum. The corpus luteum serves as secretes progesterone and some estrogen.
Now, let's discuss what happens to the released secondary oocyte after ovulation. Since the site for fertilization is the ampulla of the fallopian tube, it should reach the fallopian tube. A fallopian tube includes the infundibulum, ampulla, and isthmus. Fingerlike structures, called fimbriae are present at the lateral end of each fallopian tube that is close to the ovary. The secondary oocyte enters a uterine tube because the fimbriae sweep over the ovary at the time of ovulation. The event is assisted by the beating of cilia present in the lining of the fallopian tube.

So, the correct answer is D. Help in the collection of the ovum after ovulation.

Note:
One should understand that the phases of the ovarian cycle and uterine cycle occur simultaneously and are under the regulation of hormones. These cycles are not temporally separated. Also, the releasing hormones from hypothalamus triggers the anterior pituitary to release its hormones.