Mollusks

Phyla Mollusca

Mollusks are a common invertebrate. They are most commonly characterized for having soft bodies and a hard external or internal shell. The body plan of a mollusk consists of 4 main parts: foot, mantle, shell, and visceral mass. The mantle is a cloak-like thin layer of tissue that covers most of the mollusks body. The foot is unlike our feet, but is used for locomotion. It uses a spade shaped structure for digging, a flat structure for crawling, and sometimes tenticles to catch prey.

 

 Mollusks can reproduce sexually by external fertilization or asexually if the mollusk is hermaphroditic (has both male and female sex organs). During external fertilization they release huge numbers of sperm and eggs into the surrounding water. The eggs become fertilized and develop into larvae. In some cases where there is a hermaphroditic mollusk, individuals of this type fertilize eggs from another individual.

Some examples of mollusks are

nudibranchs

sea hares

octopi

Cite:

Pictures:

 http://scienceray.com/biology/marine-biology/mollusks-one-of-the-largest-phyla-in-the-animal-kingdom/

http://www.thefullwiki.org/Gastropod

http://scottpenny.smugmug.com/Underwater/Favorite-Photos/Macro-Photos-1/3710902_a4E68/1/483251229_Sxydq#483251229_Sxydq

http://www.divebums.com/week/2006/Jul03-2006/index.html

http://www.wonderquest.com/octopus-and-energy.htm

Info:

http://www.earthlife.net/inverts/mollusca.html

Pretice Hall Biology book