In the surgical method of birth control available for human females, the structures P in the reproductive system are cut and ligated (tied up) properly at both ends. This prevents the reproductive cell Q released by an organ R from entering the structures P so that Q is not available to fuse with another reproductive cell S coming from the male reproductive system. In this way, pregnancy is prevented.

(a) What are structures P?

(b) What is cell' Q?

(c) Name the organ R.

(d) What is the reproductive cells?

(e) What is the name of this surgical method of birth control available to females ?