The worms have a very similar digestive system to above-ground creatures. They have a mouth, esophagus, stomach, intestine and gizzard. Also, worms have a crop, which functions as a food storage compartment.
With a central ganglion (tangle of nerves) serving as a brain, the worm is very sensitive to chemicals and vibrations in the soil around it, light and moisture.
Worms are hermaphrodites, meaning they are neither male nor female. They mate by rubbing body segments NINE through 11 against each other and secreting a mucus rich in sperm. Later, the sperm will be introduced with to the eggs when the mucus is shed along the worm's body.
The earthworm doesn't have a heart. Instead, it has two long vessels that run along each of its side that dilate and contract to pump blood throughout the worms many segments.
This system works in tandem with the digestive system. Whatever the worm eats is digested, then passes into the anus, where it is cast out as castings into the soil.