On other occasions, a mini-camera was attached to a white shark. A bony fish only has one on each side. Sharks have denticles instead of scales. These can severely lacerate the skin of someone who is brushed by a shark. Sharks' teeth are replaced throughout their lives.
Sharks lack airbladders that give bony fish buoyancy.
That's why shark's liver is big and especially rich in oil, lightening its mass in the water. A shark's skeleton is made of tough but flexible cartilage. A shark's tail is asymmetrical, with the upper lobe bigger. This gives the shark, which is heavier than water, lift while swimming. While bony fish spawn, sharks copulate.