Snail is a common name that is applied most often to land snails, terrestrial pulmonate gastropod molluscs. However, the common name "snail" is also applied to most of the members of the molluscan class Gastropoda that have a coiled shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also thousands of species of sea snails and freshwater snails. Occasionally a few other molluscs that are not actually gastropods, such as the Monoplacophora, which superficially resemble small limpets, may also informally be referred to as "snails". For more information, you can click THIS LINK to visit another website.
The Cardiovascular System of SnailsA Snail has an open circulatory system which means that blood is not restricted from travelling within the blood vessels. The heart of the snail is found on the left side of the body and is made up of one auricle and one ventricle. The ventricle pumps blood through an aortic trunk to all parts of the body through a group of arteries and capillaries. From the capillaries the blood flows into various spaces in the tissues called the hemocoel. From the hemocoel blood passes into the veins and back to the auricle. The blood present in snails contains a fused compound known as hemocyanin which purpose is to transports oxygen. Hemocyanin is similar to hemoglobin which is found in human blood.
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