Provided here is a handy of printable earthworm diagrams to help you learn the structures and parts of an earthworm for your test, quiz, or biology class. An earthworm is a tube-shaped, segmented worm found in the phylum Annelida. They are commonly found living in soil, feeding on live and dead organic matter. These pictures of diagrams are useful for learning the anatomy of the earthworm, but you will also have to study the real earthworm photographs/dissection. The first one below is the simplified earthworm diagram.
You can see in the earthworm diagram above, at the front is a simple brain, but there are no eyes, ears or nose. An earthworm consists of a digestive tube housed within a thick cylindrical muscular tube that forms the body. The body is divided into segments, and furrows on the surface of the body mark the division between each segment. The first segment encloses the mouth and has a fleshy, muscular lobe on the top. All segments, except the first, have eight retractable bristles which help the earthworm to grip surfaces as it moves.
An earthworm’s skin must always be moist. This need is generally assured by the mucus the worm excretes naturally through its skin. Without enough moisture at the skin, the gas exchange can’t occur and the worm can’t breathe. Earthworms have a simple nervous system. The cerebral ganglion is connected to a ventral nerve cord that runs the length of the body.
Each segment of the body is connected to this cord, allowing earthworms to move and respond to light, touch, chemicals, vibrations and more. Circular muscles surround each segment. When earthworms squeeze these muscles, they become long and thin. Circular muscles alternate with longitudinal muscles to help earthworms move. Studying through these diagrams is a great and easy way to assess understanding of earthworm structure. Download and print the diagrams today!