The earthworm uses its skin and digestive system to provide oxygen to its cells. The skin is thin and moist and contains blood vessels near the skin’s surface. These blood vessels transport blood and oxygen to the skin. The oxygen diffuses across the moist skin and enters the worm’s body. The worm also uses its digestive system to provide oxygen to its cells. The worm swallows air into its mouth and transports the air through its esophagus and into its crop, where it is stored. When the worm needs oxygen, it contracts the crop and pushes the air into its intestine. Tiny, finger like structures lining the intestine, known as typhlosole, absorbs the oxygen from the air and transports it to the worm’s bloodstream.