How does fertilisation take place? Fertilisation occurs once in a month. Comment.

Explanation

Fertilization in human beings the sperms made in the testis of males are introduced into the vagina of the woman through penis during copulation or mating. The sperms are highly active and mobile and thus move up through cervix into the uterus. From uterus, sperms pass into the oviducts. The oviduct contains an ovum released by the ovary during ovulation. Thus, during the ovulation cycle one egg is released by either of the ovaries. The egg reaches the fallopian tube. The sperm enters the vagina during mating. From there, it enters the uterus through cervix and reaches fallopian tube. Numerous sperms reach the fallopian tube but only one sperm is required for fertilization. Since only one egg is released in a single ovulation cycle, that is, every month during a menstrual cycle (around 14th day) and ovulation cycle happens once in a month, so fertilization occurs once in a month.