CBSE Class 10 Science 2022 · Paper 31/6/2 · Question 11

(a) (i) Males: In the surgical method (vasectomy), a small portion of each vas deferens (sperm duct) is cut and the cut ends are tied. Sperms from the testes can then no longer pass along the ducts, so no sperms are transferred and fertilisation is prevented. (ii) Females: In the surgical method (tubectomy), a small portion of each fallopian tube (oviduct) is cut and the cut ends are tied. The egg released from the ovary can no longer reach the uterus, and sperms cannot reach the egg, so fertilisation is prevented. (b) Oral pills contain hormones that change the hormonal balance of the body so that eggs are not released from the ovaries. With no egg released, fertilisation cannot take place, so pregnancy is prevented. Because they change the hormonal balance, the pills can also have side-effects.