Question

Choose the correct option with respect to the assertion [A] and reason [R] given.
Assertion(A): Not all copulations lead to fertilisation and pregnancy.
Reason (R): One reason can be that sperms and ovum are not transported simultaneously to the region where fertilisation occurs.

• A. [A] is true and [R] is false
• B. [A] is false and [R] is true
• C. Both [A] and [R] are true and [R] is a correct explanation to [A]
• D. Both [A] and [R] are true but [R] is not a correct explanation to [A]

Answer 1

The correct option is C Both [A] and [R] are true and [R] is a correct explanation to [A]

The site of fertilisation is in the ampullary region of the fallopian tube Therefore, for fertilisation to take place, sperm and ovum have to be transported simultaneously to this region. It depends on the motility, size and shape of the sperm. In an ejaculate minimum, 60% of the sperms require normal shape and size. In an ejaculate, 40% of the sperms must show vigorous motility. If these two criteria are satisfied then also fertilisation again depends on the meeting of sperm and egg. Once released sperm can live up to 72 hours inside the female and the egg once released can live up to 24 hours. Since not every copulation leads to transportation of sperm and ovum to the ampullary region at the same time therefore not all copulation will result in fertilisation and pregnancy.