What are the characteristics of sharks?

First, the physical characteristics of sharks, the bones in the body are cartilage, the fish skin is tough, and there is no swim bladder.

Second, sharks are extremely sensitive in behavior, smell and taste, and are good at camouflage in the sea.

First of all, the shark's body is streamlined, with gills on both sides of the head for breathing, which is very similar to ordinary fish in appearance.

Except for a few sharks, most sharks have tough, dull gray skin and dentate scales all over their bodies, so their skin looks very rough.

Because there is no swim bladder in sharks, once they stop moving in the water, they will sink, so sharks must always swim when they are awake.

Sharks are typical large marine fish. The bones in the body are all cartilage, and the exoskeleton is very fragile, but even so, sharks still belong to the top predators in the ocean.

Sharks need to keep swimming;

When a shark swims, its body moves mainly like a snake and its tail moves forward like a paddle. Stability and control mainly use slightly vertical dorsal fin and horizontally configured pectoral fin. Many sharks can't turn back. ?

Therefore, it is easy to get caught in obstacles such as gill nets, and once caught, it is difficult to get rid of them. Because sharks have no raccoons, the proportion of these animals mainly depends on the amount of oil stored in the liver. Sharks are slightly denser than water. In other words, if you don't swim actively, you will sink to the bottom of the sea. They swim very fast, but they can only keep high speed for a short time.