Sharks have special hearing mechanisms throughout their entire body. A shark's inner ear is specially tuned to pick up low frequency sounds, such as those emitted by an injured fish seeking help.
A shark is equipped with tiny pores on the skin's surface that absorb the sound waves into the lateral line of the shark. The lateral line contains thousands of tiny hair cells as you would find in your inner ear. Not only can the shark detect prey based on these frequencies, but can also calculate the size, distance, and location of where it can be found.