Give the term / reason
a) Mechanism responsible for
parturition.
b) Role of oxytocin during expulsion
of the baby out of uterus
c) Why does zona pellucida layer
block the entry of additional sperms?
d) Sperm cannot reach ovum without
seminal plasma.
e) All copulations do not lead
to fertilization and pregnancy.
a) Parturition is carried by rapid contractions of the endometrium(innermost lining of the uterus) due to release of the hormone 'oxytocin'.
b) Please consider above mentioned answer.
c) Zona pellucida blocks the entry of additional sperms so that one ovum can fuse with only one sperm in order to maintain various characters including sex determination, Chromosomal constituents, etc...
d) Seminal plasma is rich in fructose, calcium, ascorbic acid, and certain enzymes. It provides nourishment and protection to sperms. So, without it sperms won't be able to survive.
e) All copulations do not lead to pregnancy due to contraceptives taken by the couple or due to infertility.
b) Please consider above mentioned answer.
c) Zona pellucida blocks the entry of additional sperms so that one ovum can fuse with only one sperm in order to maintain various characters including sex determination, Chromosomal constituents, etc...
d) Seminal plasma is rich in fructose, calcium, ascorbic acid, and certain enzymes. It provides nourishment and protection to sperms. So, without it sperms won't be able to survive.
e) All copulations do not lead to pregnancy due to contraceptives taken by the couple or due to infertility.