They breathe air through blowholes.
Toothed whales are predators that use their teeth to catch squid, fish, marine mammals, etc.
Baleen whales have a sieve-like structure called baleen that catches huge amounts of tiny krill for nourishment. There are 10 species of baleen whales. Baleen whales are larger than the toothed whales. The average heart rate of large whales is from about 10 to 30 heart beats per minute. The heart rate of the beluga was measured at 12-20 beats per minute.