Name the functions of the following:
(i) Corpus luteum.
(iv) Sperm tail.
(i) Corpus luteum secretes large amount of progesterone which is essential for the maintenance of endometrium of the uterus. This is formed from the Graafian follicle after it undergoes ovulation.
(ii) Endometrium is necessary for the implantation of the fertilized ovum, for contributing towards making of placenta and other events of pregnancy.
(iii) Acrosome is filled with enzymes that help in dissolving the outer cover of the ovum and entry of sperm nucleus. The acrosome is modified from the Golgi body of the cell.
(iv) Sperm tail facilities motility of the sperm essential for reaching the ovum to fertilize it. It initially shows undulating movements but after capacitation, it shows whiplash type of movements.
(v) Fimbriae are fingers-like projections at the mouth of fallopian tubules that help in collection of the ovum after ovulation and from there the ovum enters the fallopian tube.