Scales

Small protective plate in the skin of the fish.

The scales are external structures of the skin of certain animals, which allow them to protect their body from external aggressions. In the aquatic world, there are scales on many animal species, such as fish, amphibians and reptiles.

Fish scales are very characteristic structures, which cover the entire body. They are arranged to form a sort of rigid shell that protects the fish from predators and shocks. Some scales are very small and very fine, like those of flat fish, while others are larger and thicker, like those of bone fish.

Fish scales are generally two types: cyclical scales and cosmic scales. The cyclical scales are arranged in concentric circles around the body of the fish, and they are more numerous on the side parts of his body. The cosmic scales, on the other hand, are argued irregularly on the body of the fish, and they are smaller and thinner than cyclical scales.

Fish scales are made up of keratin, a protein that gives them their harshness and resistance. They are also covered with a layer of mucus that protects fish from parasites and infections.

Fish scales play an important role in regulating body temperature, thanks to their ability to reflect light and absorb heat. They also allow the fish to slide easily into water, by reducing the hydrodynamic resistance of its body.

The scales of amphibians and reptiles are very different from those of the fish. The scales of the amphibians are generally smaller and finer, and they do not cover the whole of their body. The scales of the reptiles are larger and thicker, and they generally cover the whole body of the animal.

In summary, scales are external structures of the skin that protect animals against external aggressions. They are present in many animal species, and they play an important role in regulating body temperature and in the reduction of hydrodynamic resistance.