What is tertiary egg membrane and explain?
Answers
egg membrane. Any of the protective membranes or envelopes enclosing an ovum. It may be primary (formed by egg itself, as in vitelline membrane), secondary (formed by follicle cells, as in zona pellucida), or tertiary (formed by oviduct or uterus, as in albumin and shell of hen's egg).
On the basis of origin, egg- membranes are divided into three parts
(1) Primary egg membrane: Oocyte secretes this membrane Examples: Zona Pellucida, Vitelline membrane etc.
(2) Secondary egg membrane: This is seen outside the primary egg membrane & is secreted by the ovary. Examples: Chorion, corona radiata
(3) Tertiary egg membrane: This is present outside the primarveca membrane
uterus or the oviduct. Examples: Jelly coat, Shell & Shell membrane.
Some functions of Egg-membranes are as follows:
1. To provide protection
2. To prevents the egg from dessiciation.
3. To provide buovence to the ambian exis
4. To check polyspermy.