Echinoderms Test

An echinoderm with five arms arranged around a center point.

• sea cucumber

• sea star

• sand dollar

• tube feet

How many species of echinoderms are living today?

• 3,000

• 4,000

• 6,000

• 5,000

What does the term echinoderm mean?

• tube feet

• star shaped

• spiny skin

• stomach foot

How do most Echinoderms get their food?

• They are filter feeders.

• They are scavengers.

• They are predators.

The spines on an echinoderm are actually...

• part of the skin.

• made of chitin.

• part of the endoskeleton.

• part of the water vascular system.

This water vascular system structure is centrally located, and acts like the "Grand Central Station" for water being distributed to the arms of an echinoderm.

• radial canals

• ring canal

• madreporite

• stone canal

Where do echinoderms live?

• In the ocean

• In freshwater lakes

• In freshwater rivers

• On land

Under the skin of a sea star are thousands of ________________, also known as ossicles.

• tentacles

• scales

• bony platelets

• blood vessels

Instead of a brain, sea stars have a _______________.

• Radial canal

• Nerve ring

• Heart

• Straw

The sea star's nerve ring acts to coordinate the ___________ of their arms.

• strength

• length

• movement

• color