Answer:

For flotation, sharks rely on their liver which has oil and fats.

Their liver has two parts filled with oil and fats, substances that are lighter than water helping them to float.

Liver is as much as 30% of the shark weight, and although it helps for buoyancy, sharks must swim continuously to avoid sinking.

 

 

Links to other pages in this site

What Do Sharks Eat?
What Does Shark Mean?
Why Are Sharks Going Extinct?
What Is A Whale Shark?
What Is The Age Span Of A Shark?