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How would you describe bivalves?

How would you describe bivalves?

A bivalve is an animal belonging to the class Bivalvia. Its name is a reference to the two shells, called valves, that protect its soft inner body parts. Bivalves like clams, oysters, scallops and mussels are commonly used throughout the world as a source of food for both humans and other animals.

What are examples and characteristics of bivalves?

bivalve, (class Bivalvia), any of more than 15,000 species of clams, oysters, mussels, scallops, and other members of the phylum Mollusca characterized by a shell that is divided from front to back into left and right valves.

What is a bivalve organism?

Bivalvia is a class of mollusks that all have two shells. It includes the clams, oysters, scallops and mussels. Nearly all bivalves feed by filtering tiny organisms and other bits of food from the water they live in.

What do bivalves look like?

Bivalves as a group have no head and they lack some usual molluscan organs like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders.

What are two characteristics of bivalves?

bivalve summary Clams, cockles, mussels, oysters, scallops, and shipworms are bivalves. Most are completely enclosed by the shell, the two valves of which are joined by an elastic ligament, and by two sheets of tissue called the mantle. Bivalves have no head.

Where does bivalve live?

Where did they live? Bivalves live on the bottom of rivers, lakes and seas. Some, like scallops, lie on the surface but others burrow beneath it, where they have some protection from predators.

What is the body structure of bivalves?

Bivalve molluscs are completely enclosed by a shell made of two valves hinged at the top. A hinge ligament made of elastic protein joins the two halves of the shell together, and large adductor muscles between the two valves hold them closed.

What are bivalves made of?

The bivalve shell is made of calcium carbonate embedded in an organic matrix secreted by the mantle. The periostracum, the outermost organic layer, is secreted by the inner surface of the outer mantle fold at the mantle margin.

What are the characteristics of cephalopods?

All cephalopods have the same basic anatomy. They’re made up of a body, a head and a foot. They have a muscular casing called a mantle which contains and protects their organs. They all have arms — at least eight of them — that are attached directly to their heads, but only some species also have tentacles.

How does a bivalve grow?

Bivalve shells grow by adding new material (calcium carbonate) to the edges. This leaves a pattern of fine lines (growth lines) on the exterior, that give a history of growth (much like tree rings on the inside of a tree). On the inside, the shell has a set of interlocking pegs (teeth) and sockets that form the hinge.

What is difference between bivalves and univalves?

Bivalves consist of two shells. Unlike the univalve type of mollusk, the bivalves generally do not have a head, just the body that resides in between the two shells that open and close at will, usually to feed.

What are the four main characteristics of bivalves?

Intelligent,well developed nervous system X

  • Has no distinct head X
  • Has an open circulatory system X X
  • External shells present in some species X X X
  • Bite prey with beak X
  • Uses gills for both respiration and food collection X
  • All species are carnivorous predators X
  • Uses a radula for feeding X
  • Can change color for camoflauge X
  • Can form pearls X
  • How are bivalves different from other mollusks?

    The sedentary habits of the bivalves have meant that in general the nervous system is less complex than in most other molluscs. The animals have no brain; the nervous system consists of a nerve network and a series of paired ganglia. In all but the most primitive bivalves, two cerebropleural ganglia are on either side of the oesophagus.

    Bivalves are the common sea shells that we find on the beach (see left). Bivalves look like brachiopods, with pairs of shells, but bivalve shells are usually lop-sided rather than symmetrical, and both shells tend to look the same.