How long should a refrigerator last? This questions is asked so many time, again and again. Most refrigerator keep operational more than 10 years. A survey conducted by the appliance magazine found out that 80% of refrigerators last 8-14 years.
There are 5 main classes of mollusks, and two smaller classes that most people have never heard of. The principle classes are: Gastropoda (gastropods) - snails, slugs, conchs, whelks, cowries, etc. Bivalvia (bivalves) - clams, mussels, oysters, cockles, scallops, etc. just now. Report Abuse. The living mollusks are placed into seven classes (some workers combine the Solenogastres and Caudofoveata into a single class called Aplacophora): Solenogastres Caudofaveata Polyplacophora Scaphopoda Cephalopoda Bivalvia Gastropoda There are over 50,000 different types of mollusks alive today.
Remove these ads. 1  Common types of shells include sea shells, snail shells, turtle shells and eggshells. 2  There are more than 50,000 varieties of mollusk shells. 3  Some open like clam shells, while others are shaped in a spiral and have a single hold where the animals enters and exits the shell.