Chapter 10 Flashcards
True/False
Molluscs are important to humans because of their important ecological niches, because a variety of them are eaten, and because some kinds produce pearls.
True
The pulmonate snails lack gills, and their mantle cavity functions in an analogous fashion to a ______.
Lung
Most cephalopod molluscs can change colors because of special pigment cells that are called ______.
Chromatophores
The circulatory system of cephalopods is more efficient than that of other molluscs because
It is closed
The tongue-like, rasping organ in the head of most molluscs is the _______.
Radula
The group of molluscs which are most endangered are the
Freshwater bivalves
True/False
Some bivalves have an operculum which prevents drying when the tide goes out
False
The characteristics that generally typify molluscs are
Radula, open circulation, mantle, shell.
True/False
The mantle cavity in a molluscs houses the gills, foot, and head
False
Locomotion in most of the Bivalvia is accomplished by
A muscular foot
Torsion in gastropods caused the mantle cavity and the organs it contained to lie above the
Head
Most molluscs are found in fresh water, but a few live in the ocean or on land
False
The edible clams, oysters and scallops belong to the class
Bivalvia
The water current in the body of a cephalopod mollusc provides
All of the above
A means of carrying wastes and gametes out of the body, oxygen for respiration, jet power for rapid locomotion
The molluscs are the second most diverse phylum known
True
