How many kinds of fingerprints are there?

There are three types of fingerprints:

1. There are concentric circles or spirals, which look like swirls in water, called spirals); ;

2. Some lines are open on one side, which is like a dustpan, called a loop;

3. Some patterns are like bows, called arches.

Besides the overall shape, the number and length of fingerprint patterns are also different.

Fingerprints, also known as handprints, are ridges protruding from the epidermis. Because people's fingerprints are generated by the interaction of heredity and environment, everyone has fingerprints, but they are different. Because the fingerprint repetition rate is very small, about 654.38+0.5 billion, it is called "human ID card".

Fingerprint is a line formed by the concave and convex skin of human fingertips. Fingerprint can increase the friction when the hand touches the object, so it is easier to exert force and grasp the object. It is naturally formed in the process of human evolution.

Extended data:

The formation of fingerprints:

In the process of skin development, although the epidermis, dermis and matrix layer all grow together, the soft subcutaneous tissue grows faster than the hard epidermis, so it will exert a steady upward pressure on the epidermis, forcing the slower epidermis to contract and collapse towards the internal tissue, and gradually bend and wrinkle, so as to reduce the pressure exerted by the subcutaneous tissue.

On the one hand, it is hard to attack, on the other hand, it is forced to withdraw, which leads to uneven skin and lines. This process of bending and wrinkling fluctuates with the change of the upward pressure generated by the internal tissue, forming uneven ridges or wrinkles until the development process stops, and finally it is shaped into a fingerprint that will remain unchanged until death.

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