Exam 16: Molluscs

Describe five features,morphological or developmental,that would most likely be found in the earliest ancestral mollusc.

The Scaphopoda

Clams burrow by using

The Polyplacophora

Cephalopod eyes and vertebrate eyes are anatomically similar.Evaluate whether or not the similarity is a case of homology or analogy.State your reasoning.

Because shells require it,land snails are limited to soils that contain some level of

The nudibranchs belong to the

You find an old living freshwater clam.The health department would like to check a small sample of the shell for pollutant levels when it was young.Where should they remove this oldest shell material?

What are the morphological features that distinguish the ammonoids from the nautiloids?

Give the supporting evidence that shows that the molluscs share a common ancestor with the annelids.

In some molluscs,the free-swimming larva is a trochophore while in others,it is a veliger with the beginnings of a foot,shell and mantle.What is the relationship of these molluscan juvenile stages?

The solenogasters

To prevent taking back in the wastes it has just expelled,a standard sediment-inhabiting bivalve mollusk should position itself

Molluscs with a tubular shell that open at both ends are in the class _____________________.

How does torsion differ from coiling? Fully explain your answer.

Most cephalopods have an ink gland that secretes ______________,a dark fluid containing melanin,to confuse enemies.

Although snails and some other molluscs are hermaphroditic,most molluscs are either male or female,a condition called

Gaseous exchange in gastropods may involve

Snails were discovered in the Negev desert at night,harvesting the lichens that grew in the moist pores of the limestone and wearing down the desert more than abrasion from wind.Scientists studying these snails added mild acid to the snail feces and it foamed;this was an important test to detect that