Earthworm Dissection

Leeches have setae.

• True

• False

The clitellum is part of the nervous system.

• True

• False

The body of an earthworm is supported by an internal skeleton of bone.

• True

• False

An earthworm has a closed circulatory system.

• True

• False

Name (in order) the seven structures of the earthworm digestive system.

• Mouth → pharynx → esophagus → crop → gizzard → intestine → anus

• Mouth → esophagus → pharynx → crop → gizzard → intestine → anus

• Mouth → pharynx → crop → esophagus → gizzard → intestine → anus

• Mouth → pharynx → esophagus → gizzard → crop → intestine → anus

Name the four components of the earthworm nervous system listed in the guide.

• brain, ventral nerve cord, lateral nerves, dorsal nerve cord

• brain, dorsal blood vessel, crop, gizzard

• Clitellum, setae, crop, gizzard

• brain, lateral nerves, clitellum, dorsal blood vessel

The primary excretory organ in each segment of the earthworm is the _____.

• nephridium

• gizzard

• crop

• clitellum

An animal that has both male and female reproductive structures is called a _____.

• hermaphrodite

• larva

• predator

• detritivore

Select all features of annelids listed in the guide.

• Segmented body plan, complete digestive system, segments divided by septa

• Closed circulatory system, presence of longitudinal and circular muscles

• setae, hydrostatic skeleton, excretory system of nephridia

• Hydrostatic support within a true coelom

Match each earthworm structure to its function.

• circulates blood

• Gizzard

• grinds food

• Dorsal blood vessel

• bristle-like structures for burrowing

• Setae

• receives sperm during copulation

• Seminal vesicle

• produces and stores sperm

• Seminal receptacle