Answer:
a. will contain either a Y chromosome or a X chromosome but not both.
c. reach maturity in the seminal vesicles.
d. contain enzymes in their heads which facilitate penetration of ovum.
Explanation:
Spermatogenesis is a complicated process. It occurs in the seminiferous tubule / seminal vesicle of the testis. The spermatogenesis occurs in 2 steps. In the first step, spermatids are produced. In the second 2nd step, spermatids undergo metamorphosis and form spermatozoa.
The process of formation of spermatozoa is known as spermatogenesis. These are formed from the primary germ cells of the testis. It occurs in 3 phases- multiplication phase, growth phase, and maturation phase.
The maturation phase is important. Here primary spermatocyte divides 2 times. The first division is a meiotic division that produces 2 haploid cells, called secondary spermatocytes.
The second division is a mitotic division. Thus from 2 secondary spermatocytes, 4 spermatids are formed. Further by metamorphosis, the spermatids result in spermatozoa. The spermatozoa have 4 parts - head, neck, middle piece, and a tail. The head is a conical shape. It consists of a nucleus and acrosome.
Acrosome is also called head cap. It secretes a tissue dissolving enzyme which helps to rupture the egg cell. Thus the sperm can penetrate the ovum.