Sea Star Dissection

Sea stars are in which phylum?

• Chordata

• Echinodermata

• Arthropoda

• Cnidaria

What type of symmetry do sea stars exhibit?

• Asymmetrical

• Bilateral

• Radial

Where are sea star eyespots located?

• On top of the central disk

• On their face

• On the tips of their arms

• They don't have eyes

What should you look for to locate the madreporite?

• A hard, white bump on the central disk

• A large hole on the aboral surface

• An extra squishy area on top of each arm

What is the function of the spines? 

• Feeding

• Protection

• Mating

How is the sea star is able to eat clams and other food items that are larger then the opening of its mouth?

• It is able to push its stomach out of its mouth to engulf & digest food

• Its oral spines cut food into tiny pieces to bring into the mouth

• The oral spines slowly scrape off small amounts of food

Tube feet are located in the openings on the underside of the sea star known as the ____________

• spine grooves

• water vascular grooves

• ambulacral grooves

What is the purpose of the internal skeleton (endoskeleton)? 

• Provide respiration and circulation

• Provide protection and rigidity

• Provide a way to capture food

What is the function of the digestive gland? 

• They secrete digestive enzymes and then absorb nutrients digested in the body to allow for digestion outside the body

• They help to distribute wastes to the anus for removal from the body

• They help to transport sperm or eggs to be released from the body

Where are the gonads located in the sea star?

• below (ventral to) the stomach in the central disk

• in each arm, underneath (ventral to) the digestive glands

• in each arm, on top of (dorsal to) the digestive glands