Student to attempt either option (A) or (B). (A) (i) Draw a diagrammatic sectional view of human seminiferous tubule (enlarged) and label the…

$\displaystyle \star$ Secretions of male accessory glands (prostate, bulbourethral glands and seminal vesicles) constitute the seminal plasma.

$\displaystyle \star$ Seminal plasma is rich in fructose, calcium and, certain enzymes

$\displaystyle \star$ Seminal plasma along with sperms constitutes the semen.

Entry of sperm into the cytoplasm of the ovum induces the completion of second meiotic division of the secondary oocyte.

As the zygote moves through the fallopian tube the mitotic divisions (cleavage) start, it results into $\displaystyle 2$ -$\displaystyle 16$ daughter cells called blastomeres , Embryo with $\displaystyle 8$ to $\displaystyle 16$ blastomeres is called morula , Morula continues to divided and form Blastocyst which moves further into uterus, The blastomeres in the blastocyst are arranged into an outer layer trophoblast and an inner group of cells called the inner cell mass, the trophoblast gets attached to the endometrium, and the inner cell mass gets differentiated as the embryo, the uterine cells divide rapidly to cover blastocyst which gets embedded in the endometrium and this is called as implantation