Mollusks in the classes gastropod (snails, slugs, nudibranchs) and bivalves (clam, mussels) move with a muscular foot. In the class of cephalopods, the foot has become 8 tentacles and no longer is used for movement. In this case, they use jet propulsion and water propels them away from predators or towards prey.

Snails are born with their shell. As the snail grows, so does its shell -- in a spiral shape. New shell is added at the opening of the shell by the mantle. In the center of the spiral is the part of the shell that the snail began life with.

The shell is made from several layers. The thin outer layer is made from an organic substance known as conchiolin. The thicker layer underneath is formed from three layers of crystalline calcium carbonate, similar to the chicken egg of which you may be more familiar. The color of the shell depends on the types of food the snail is eating and also the type of snail.

The red abalone can be 8 to 12 inches (31 cm) in size.

Sea Urchins role in the ecosystem is to provide a canopy habitat for larval, juvinile and some adult fish and invertebrates to hide and grow under until they are large enough to emerge safely. Sea Urchins are algae and detritis eaters which keep a balance in the benthic habitat by grazing on which if left can cause spikes in bacteria levels or in the case of coral reefs can smother coral. They move around and clean up the bottom. Lastly Sea Urchins are a food source for humans, fish and other animals. Sea Urchins can very easily overpopulate and if they do can wreak havoc in large areas in the ecosystem, particularly inside of Marine Reserves. Little is known about this phenomena of Sea Urchin Barrens other than that they can last for decades until a disease hits and there is a mass die off. In California, habitat restoration efforts are underway to eradicate these Sea Urchin Barrens or Urchin Dominated Areas by Santa Monica Baykeeper and the Orange County Baykeeper. It seems ironic that they would advocate for Marine Reserves in the MLPA process which in effect causes Sea Urchin Barrens that contradicts their efforts to restore the habitat that they have or about to destroy. Look on u tube for the Baykeepers videos and also for other sea urchin barrens videos.

Because in the wild 99.9% of them (or so) get eaten. So in numbers there is strength....and survival. IT IS SO LAME!!!!

Mollusk is an invertebrate animal. Some mollusks are covered with shell and some has tentacles. Mollusk are soft-bodied invertebrate animal. Examples are octopus, snail , oyster and clam.

-Co0leTs24

Mollusks compose of the large phylum of invertebrate animals known as the Mollusca. Mollusks have a mantle, mollusks invertebrate. Arthropods have jointed appendages, arthropods have segmented bodies

A mollusk usually weighs just a few ounces, but more when they are stuffed and ready to be eaten!

Slugs, snails, squid, and octopus are common Mollusk.

Visceral mass of mollusks contain all organs but head foot and gills . Thus vascular , excretory reproductive , part of nervous and digestive functions function are performed by visceral mass .

Most shellfish should not be reheated, as the threat of botulism is high for them.

A stomach-footed mollusk has a shell to protect its self, tentacles to smell, mouth to eat, foot on bottom of stomach to move, and a head with two eyes on the ends.(ex. snails, slugs, and conchs)

They hold onto the sand with their sticky feet.

Trochophore

Depends on the type of mollusk.

Clams and oysters and scallops generally filter nutrients such as plankton out of the water. Some giant clams also have symbiotic algae growing in their flesh (zoothanthellae) that also contribute to their nutrition.

Some molluscs are fierce predators as well- octopi, squid, cuttlefish, conch, cone shells, and others- they will eat pretty much whatever they can catch. (And several are actually venomous! A sting from a cone-shell can make you very very sick indeed, or even be fatal!)

(Biology teacher/Professional Naturalist)

Molluscs eat all kinds of things. The cephalopods (octopi, squids, and their allies) are predators of fish and other marine life. Most bivalves are pretty much herbivorous, feeding primarily on phytoplankton, though some are predators. The gastropods are also mixed, with some herbivorous, such as abalones, and some carnivorous predators, such as moon snails, oyster drills, and cone shells. Incidentally, some cone shells (Family Conidae) are poisonous enough to kill people! They also eat snails.

yes they are invertebrates with exskeletons

yes why wouldn't it :D

visceral mass

The presence of he shell, the type of shell, the type of foot, and the type of nervous system

snails and mosquitos can both play host to very nasty viral or parasitic passengers. snails can carry a parasite the causes schistosomiasis and different mosquitos can carry anything from dengue fever to yellow fever to malaria to west nile virus to philariasis.

schistosomiasis is very treatable if caught before late stages where as malaria, west nile, or dengue can cuase death very rapidly, some cases even 24 hours.

Protection from enemies. Squids spray their ink to create a cloud that distracts a predator long enough that allows the them to escape