Answer:
The egg is made by the hen. It creates an embryo (the future chick, the little white spot that you see on the egg yolk) which will be fed by the yolk of the egg.
The yolk is a food reserve (called the yolk) for the chick in formation: by eating the yolk, the embryo becomes a chick.
The white consists of gelatinous proteins, which the future chick will eat during incubation, warm for 21 days under the hen.
The shell protects the embryo, the yolk and the white. It is made of two membranes that are made from calcium that the hen stores in her bones and intestines. In the chicken's belly, muscles spin the egg during training and give it its perfect shape.
The shell is made in such a way that it is difficult to the pan from the outside, but very easy to break it from the inside. So the hen does not crush her eggs when she is brooding, but the chick can come out easily!
It works pretty much the same for all birds, reptiles, fish ... that lay eggs. On them, moreover, oviparous animals.
Explanation:
