Adult cats average about 8 to 10 inches (20 to 25 centimeters) tall at the shoulder. Most cats weigh from 6 to 15 pounds (2.7 to 7 kilograms). Some cats weigh more than 20 pounds (9 kilograms).
Cats have the same basic skeleton and internal organs as human beings and other meat-eating mammals. The skeleton of a cat has about 250 bones. The exact number of bones varies, depending on the length of the cats tail. The skeleton serves as a framework that supports and protects the tissues and organs of a cats body. Most of the muscles attached to the skeleton are long, thin, and flexible. They enable a cat to move with great ease and speed. Cats can run about 30 miles (48 kilometers) per hour.
The arrangement of the bones and the joints that connect them permits a cat to perform a variety of movements. Unlike many animals, a cat walks by moving the front and rear legs on one side of its body at the same time, and then the legs on the other side. As a result, a cat seems to glide. Its hip joint enables a cat to leap easily. Other special joints allow a cat to turn its head to reach most parts of its body.
A cat has five toes on each forepaw, including a thumblike toe called a dewclaw. Each hindpaw has four toes. Some cats have extra toes. Each of a cat's toes ends in a sharp, hooklike claw. The claws are usually retracted (held back) under the skin by elastic ligaments, which are a type of connective tissue. However, when the claws are needed, certain muscles quickly pull the tendons (cordlike tissues) connected to the claws. This action extends the claws. A cat uses its claws in climbing, in catching prey, and in defending itself. Several spongy pads of thick skin cover the bottoms of a cat's feet. The pads cushion the paws and enable a cat to move quietly.
A cat's tail is an extension of its backbone. The flexible tail helps a cat keep its balance. When a cat falls, it whips the tail and twists its body to land on its feet.
A cat's head is small and has short, powerful jaws. Kittens have about 26 needlelike temporary teeth, which they shed by about 6 months of age. Adult cats have 30 teeth, which are used for grasping, cutting, and shredding food. Unlike human beings, cats have no teeth for grinding food. But a cat's stomach and intestines can digest chunks of unchewed food. Tiny hooklike projections called papillae cover a cats tongue, making it rough. The rough surface helps a cat lick meat from bones and groom its coat.