Question

For ovulation in reflex ovulators
A) Coitus is necessary
B) Coitus is not necessary
C) Plenty of food is not necessary
D) Plenty of food is necessary

Answer 1

Hint: Reflex ovulators have a unique ovulatory mechanism. The ovulation is stimulated by the stimulus generated by mating.

Complete Answer:
Ovulation is the process of the release of female egg cells from the ovary follicle to the surface of the ovary. Different species have different types of ovulation mechanisms. Different types of ovulation are-
1) Spontaneous ovulation is the ovulatory process in which the maturing ovarian follicle secretes ovarian steroids to generate neuropeptide responsible for controlling reproductive functions. It releases into the hypothalamus to cause a LH surge. Species in which females are spontaneous ovulators are rats, mice, sheep.
2) Induced ovulation is induced when a female ovulates due to an external stimulus during or prior to mating rather than ovulating cyclically or spontaneously. Steroid induced surges are not seen in induced ovulation. Species like cats, rabbits undergo induced ovulation. Stimuli can be a physical act of coitus, mechanical stimulation, sperm or pheromones.

Additional Information: Induced ovulation is prominent in those species that have shorter life span. This adaption is to bridge the various mating chances in a short life span.

Thus the correct answer is (A) for ovulation in reflex ovulators coitus is necessary.

Note: Induced ovulation or reflex ovulation occurs in response to external stimuli like pheromones, coitus. It is more common in cats, rabbits. Humans do not show induced ovulation. Rather they undergo spontaneous ovulation.