Question

What type of circulatory system do mollusks have? Which animal in this phylum is the

exception?

Answer 1

Molluscs, with the exception of cephalopods, have an open circulatory system, i.e., the blood circulates within vessels, from the heart, but it also fills open lacunas or cavities.

Answer 2

Molluscs with the exception of cephalopods have an open circulatory system I.e.the blood circulates with in vessels from the heart but it also fills open lacunas or cavities. In annelids the cieculatory system is closed, i.e. the blood circulates only inside blood vessels.