Question

Vitelline membrane is a
Option A- Primary egg membrane
Option B- Secondary egg membrane
Option C- Tertiary egg membrane
Option D- None of the above

Answer 1

Vitelline membrane is the transparent casing that encloses the yolk of the egg of the hen and separates it from the albumen, albumen is the white part of the egg. Vitelline means having a colour yellow that resembles yolk of the egg.

Complete answer:
Vitelline egg membrane is the extracellular protein membrane that covers the yolk. Vitelline membrane is made up of glycoproteins. This membrane contains receptors that are required for sperm binding. There is the same type of membrane in mammals also known as Zona pellucida.

Option A- Primary egg membrane: Primary egg membrane develops in the ovary and this membrane covers the egg membrane. This primary membrane is known as vitelline membrane in insects, birds, mollusks, amphibians. This primary membrane in mammals is known as zona pellucida.

Option B- Secondary membrane: The membrane formed as a basement membrane by a layer of the follicle cells surrounding the ovum is secondary membrane. This membrane is also called as chorion and is secreted by auxiliary cells of the ovary.

Option C-Tertiary membrane: This is the membrane that is secreted by the cells of the female genital’s tract when ovum moves along the oviduct.

Option D-None of the above- Vitelline membrane is another name of primary egg membrane so none of the above is not the correct option.

So our correct answer is Option A- Primary egg membrane.

Note:
Vitelline membrane is composed mainly of protein fibers and it contains protein receptors also that are required for the binding of the sperm and in turn bound to sperm plasma membrane receptors. The specificity of species between these receptors prevents breeding between different species.