Question 2
What is the role of the seminal vesicles and the prostate gland?

Seminal Vesicle secretes a fluid which forms a major part of the semen (60%). Its secretion is alkaline in nature whose role is to neutralise the effect of acid in the female genital tract. Its secretion contains fructose sugar which provides nutrition and immediate energy to the sperm.

Prostrate Gland also secretes a fluid which forms 13-33 % of the remaining semen providing an aqueous base for the sperms to swim. It also promotes viability by helping the sperms of positively strike the ovum.
The secretions of both the seminal vesicle and the prostate gland ensure that the semen remains in a fluid state.