What do cetaceans eat?

The toothed whales, including dolphins and porpoises, use their teeth to capture their prey, which is usually fish, squid, seals, and other marine animals.  They eat their prey whole or rip large chunks off with each bite if the prey is large.  The baleen whales have baleen plates in their mouth that hang from the upper jaw.  These plates are made of keratin, which is what human finger nails are made from, and they act as a filter, allowing small fish and krill to pass through into the mouth of the whale.