Question

Which event is not associated with ovulation in human females?
A. Decrease in Estradiol
B. Full development of Graafian Follicle
C. Release of secondary oocyte
D. LH surge

Answer 1

Ovulation refers to the release of an egg during menstruation in females. It is also termed as ‘Fertile window. A woman is most fertile around this time. There are three different phases occurring during ovulation; follicular phase, ovulatory phase and the luteal phase. Recall the functions of each and every option given and eliminate the wrong one accordingly.

Complete answer:
- Ovulation is the release of an egg from one of the fallopian tubes, after its release, where fertilization of egg occurs by a sperm cell.
- Ovulation typically occurs in the middle of a woman’s menstrual cycle, i.e; around 13 to 15 days of the cycle. But for each woman, it depends upon the length of her menstrual cycle. Typically, the menstrual cycle ranges from 28 to 35 days.
- During ovulation, when the level of estrogen reaches its peak, it produces a sudden release of LH, around 13th cycle day. The LH surge triggers a complex set of events within the follicles resulting in the maturation of the egg and follicular collapse with egg extrusion. Ovulation takes place 28-36 hours after the onset of LH surge. The cells in the ovarian follicle that are left behind after ovulation undergo a transformation and become ‘Corpus luteum’.
- Thus it is clear that except (A), all the other events occur during the ovulation in human females. ‘Estradiol’ levels are not associated with ovulation. Decrease in estradiol levels is associated with the cessation of menstruation.

Hence, the correct answer is option (A).

Note: The estradiol is known to be a female sex hormone and so the secondary sexual characteristics are also in its control. It has many important tasks such as protecting the lining of vagina, fallopian tubes and endometrium. The ovulation process generally stops after menopause that is between 45 to 50 years. Problems with ovulation cause infertility issues such as polycystic ovarian syndrome, hypothalamic dysfunction, excess prolactin and many others.