Mollusks

Content

• Types of mollusks
• Morphology
• Feeding
• Habitat
• Examples of mollusks

Mollusks are invertebrate animals that are characterized by having a soft body with a muscular foot covered by a calcium-based exoskeleton or shell. They are usually aquatic animals.

Types of mollusks

There are three different classes or types of mollusks:

• Gastropods. Snails and slugs. About 80% of mollusks are of this class.
• Cephalopods. Octopus, squid and cuttlefish. It is a less numerous group but much more evolved.
• Vivalves. In this group are clams, mussels and oysters. The characteristic of this subgroup is that they are the only ones of the three subtypes that do not have a radula. Clams, mussels and oysters. They are the only ones who do not have a record.

Morphology

• Respiratory system. Most mollusks breathe through gills, although some species have developed a pulmonary respiratory system.
• Digestive system. Mollusks feed through an organ called radula which is shaped like a tongue. Also called the mantle, this organ covers the visceral mass and in some species secretes calcium carbonate to form the shell.
• Circulatory system. They have a heart, aorta, and blood vessels.
• Reproductive system. Mollusks are oviparous, that is, they reproduce by laying eggs by the female. Their behavior is solitary, it is not frequent to see them in groups, except when they are mating. Many mollusks are hermaphrodites.

Feeding

The type of feeding of the mollusks varies according to each species. Generally, land mollusks are herbivores, while aquatic mollusks are carnivores, although they also base their diet on plankton and algae.

Habitat

In relation to their habitat, mollusks can live under water, at the bottom of the sea (they constitute 23% of all marine and freshwater animals), but they can also get used to and live at 3000 meters above sea level. .

Examples of mollusks