Question

Hen’s egg is
A. An organ
B. A single cell
C. A tissue
D. None of the above

Answer 1

Hint: The yolk of a hen’s egg is basically an oocyte (an immature ovum). The yolk develops into a complete egg which when not fertilised, passes through a chicken’s vagina as it is.

Complete answer:
The correct option is B.
The process of egg development inside a hen’s body takes place in multiple stages. The yolk is produced from the ovaries by ovulation. The yolk is an oocyte and regardless of being fertilised or not, upon its release it travels down the oviduct.
As soon as the egg arrives at the magnus, a part of oviduct, a vitelline membrane is added to the yolk along with other necessary fibres and albumin layers (thick albumin and thin albumin), which constitute the ‘egg white’.
Rotational mechanisms make sure the yolk is well anchored in the egg white through chalazae fibres by the time it reaches isthmus. Just before its laid, egg shell membranes are added to the egg along with shell pigments in the isthmus.
The shell is made of a crystalline calcium carbonate compound called calcite. The egg is plunged out of the vagina with a larger end downwards.

Note: It is noted that, a chicken’s or hen’s egg although significantly large and visible to the naked eye unlike human egg , just like any other ova, is a single celled structure in an unfertilised condition, when the hen hasn’t mated. In case of a fertilised egg, the laid egg is a zygote and a proper embryonic development of the embryo takes place.