(a) Seminal Vesicles: They secrete 60-70% of semen plasma that is alkaline and viscous having fructose (for nourishing the sperms), fibrinogen, proteins and prostaglandins. Prostaglandins cause movements in the genital tract of the female. Sperms are also activated by secretion of seminal vesicles.

Prostate Gland: It produces 20-30% of semen plasma. The secretion is alkaline and viscous. It has clotting enzyme and chemical essential for sperm activity.

(b) Function of Testes,

Formation of sperms from germinal cells of seminiferous tubules.

Secretion of testosterone by Leydig cells present in the connective tissue in between the seminiferous tubules.