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Class Gastropoda. The Univalves Zoology. Class Gastropoda. Class Gastropoda is the largest and most diverse group of mollusk. Over 70,000 living gastropod species are still currently found on earth today. Over 15, 000 fossil species have been discovered. Class Gastropoda.
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Class Gastropoda The Univalves Zoology
Class Gastropoda • Class Gastropoda is the largest and most diverse group of mollusk. • Over 70,000 living gastropod species are still currently found on earth today. Over 15, 000 fossil species have been discovered.
Class Gastropoda • Class Gastropoda includes snails, limpets, slugs_, whelks, conchs, periwinkles, sea slugs, sea hares, and sea butterflies.
Gastropod Homes • Gastropods live in aquatic and terrestrial environments. Gastropods that live on land have adapted an area in their mantle into a lung so that they can breathe out of water.
Univalves • Gastropods are univalves, which means that they have one shell. • The shell is made of one piece and may be coiled or uncoiled. • The apex, or center of the shell is the oldest part of the shell. • The spirals on the shell are called whorls. Whorls may curl to the right or left depending on the genetic makeup of the gastropod.
Gastropod Bodies and Torsion • Gastropods are primarily bilaterally symmetrical. • However, the middle part of their body is asymmetrical because of torsion, which is a process that twists the mantle cavity 180 degrees relative to the head and foot. • Gastropods are the only mollusk that undergo torsion.
Gastropod Defense • Gastropods defend themselves by two primary ways: their shell and their mucus. • Gastropods also have symbiotic relationships with some Cnidarians. In some cases, the gastropod can control the Cnidarian’s stinging tentacles to defend against predators.
The Gastropod Diet • Gastropods are primarily grazers. They are primary consumers in their ecosystem because they feed on plants. They use their radula, which is a combination of a tongue and teeth, to cut and scrape food.
Pesky Little Pests • Gastropods are a garden pest because they often eat landscaping plants and their population can be hard to control through conventional pesticides.
Salt and Snails…. • Snails lose the water in their bodies through the diffusion of water, or osmosis, when salt is poured on their body. Water leaves the body cells of the snail to balance the salty environment.