What is the primary function of the water vascular system in echinoderms?

Place the below phases of ecdysis in order (you cannot drag and drop the answers, click the dots to the right and it will give you the option to move them up and down):

Match the segment of the mollusc shell to its description:

The is a thin walled storage structure while the is a muscular grinding structure utilized by annelids for digestion. 

Which term below describes a fluid-filled cavity that contains visceral organs and forms a hydrostatic skeleton? 

Sclerotization is a term that refers to which process in arthropods? 

Which of the below terms describes the radical change in boy form and physiology as a larva becomes an adult?

What distinguishes male and female roundworms? 

Which of the below structures are responsible for filtering blood and making dilute urine for excretion?

Match the following arachnid adaptations to their description: