Sperm whale . Myoglobin, which stores oxygen in muscle tissue, is much more abundant than in terrestrial animals. The blood has a high density of red blood cells, which contain oxygen-carrying haemoglobin. The oxygenated blood can be directed towards only the brain and other essential organs when oxygen levels deplete. The spermaceti organ may also play a role by adjusting buoyancy (see below). The arterial retia mirabilia are extraordinarily well-developed. The complex arterial retia mirabilia of the sperm whale are more extensive and larger than those of any other cetacean. Atop the whale's skull is positioned a large complex of organs filled
Right whale whales have a distinctive wide V-shaped blow, caused by the widely spaced blowholes on the top of the head. The blow rises above the surface. Right whales have between 200 and 300 baleen plates on each side of their mouths. These are narrow and approximately long, and are covered in very thin hairs. The plates enable the whale to filter feed. The penis on a right whale can be up to – the testes, at up to in length, in diameter, and weighing up to 525 kg (1157 lbs), are also by far the largest of any animal on Earth.