Name the functions of the following.
(a) Corpus luteum
(b) Endometrium (c) Acrosome
(d) Sperm tail
(e) Fimbriae

Explanation

(a) Corpus Luteum. It secretes progesterone hormone which prepares the endometrium of uterus for implantation, placentation and normal development of foetus. So it maintains the pregnancy. (b) Endometrium. It is the innermost, highly vascular and glandular lining of uterus. It undergoes cyclic changes during menstrual cycle and prepares itself for implantation of blastocyst and placentation. (c) Acrosome of head of sperm secretes sperm lysins like hyaluroindase (which dissolves hyaluronic acid of egg locally), corona penetrating enzyme (which dissolves corona radiata) and acrosin (which dissolves zona pellucida). (d) Sperm tail. It shows lashing movements which provide forward push to the sperm. (e) Fimbriae are finger-like processes of fallopian tube which increase the chances of trapping of ovum released from the ovary.