Kategorier: Alle - adaptability - invertebrates

af Hugo Gomez 8 år siden

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Molluscs

Terrestrial molluscs, including snails and slugs, are a diverse group of invertebrates that have adapted to life on land. They usually possess a lung for breathing and often feature a coiled shell for protection.

Molluscs

TERRESTRIAL MOLLUSCS

An invertebrate of a large phylum which includes snails, slugs, mussels, and octopuses. They have a soft unsegmented body and live in aquatic or damp habitats, and most kinds have an external calcareous shell

the main types of molluscs

If they are terrestrial they breathe with a lung,if they are aquatic they use gills.Most gasthropods are hervibores.
Subtema
most of them have a shell coiledin a spiral shape,large muscullar foot,they have a welldeveloped head ,in the mouth they have a scraper organ

The main types of molluscs

Gastrops The bivalves and the cephalopods

Terrestrial molluscs are invertebrates with bilateral simmetry that in most cases have a protective shell.

Characteristics of molluscs: unsegmented soft body most have internal or external shell have a mantle - a fold in the body wall that secretes the hard prtesctive shell muscular foot and/or tentacles have a radula - a toothed structure used to grate food two pairs of gills except in polmonate snails

Adaptations that made terrestrial life possible: Their great adaptability has made terrestrial snails one of the most successful animal groups on the earth: Falkner (1990) states a number of around 25,000 species worldwide.Numerous special adaptations have made this possible for snails, to which the dry land as a matter of fact is really dry.

Parts of the molluscs and definitions :

Muscullar foot: is a different shape for different groups,and used for movement digging or catching prey.
Visceral mass: where the internal organs are found,is covered with a sheet tissue colled the mantle.
A head: which contains sense organs for exploring their environment