Why do hair be curly?

Crispy hair is a matter of envy of many women. But why some of the nature go crispy hair, and others have to create curls on their own?

In fact, it all depends on the molecular composition of the hair. If the molecules in the hair structure are located with a smooth line, then the hair is growing straight. It happens that molecules are located in a chaotic order, it is such a order that makes the hair to melt.
Directly with the molecular composition, the waves on the hair corresponds to the hair form. If one hair is considered in detail under the microscope, then you can see it in the context. The hair is round, oval and flat. It is flat hair that go out, and a smooth perimeter - no. You can spend a small experiment: one hair take into hand, dramatically spend nails on it and it will become. Check!

A source: hochu.ua

In rare cases, a hormonal background can affect hair. In this case, straight hair will become curly and vice versa.
It also depends on the ion connection in the hair structure. With destroyed ionic connections, hair becomes curly. If with the help of certain chemical compositions to restore ion connections, then curly hair will become straight. It is due to the impaired integrity of the hair structure, curly hair require more care.