How do bivalves feed?
Like fish, bivalve mollusks breathe through their gills. As filter feeders, bivalves gather food through their gills. Some bivalves have a pointed, retractable “foot” that protrudes from the shell and digs into the surrounding sediment, effectively enabling the creature to move or burrow.
How do sponges bivalves and some worms feed?
Bivalves feed on plankton, as well as benthic algae and detritus, and in turn they provide food for echinoderms, fish, birds and other animals. Other filter feeders use an external filter. When the net is fully loaded with food, the worm swallows the food along with the net, and then makes a new net.
How do mollusks and bivalves commonly feed?
HOW DO MOLLUSKS FEED? Most mollusks have a rasping tongue called a radula, armed with tiny teeth. This scrapes tiny plants and animals off rocks or tears food into chunks. Bivalves, such as oysters and mussels, filter food particles from the water with their gills.
What type of fertilization is predominant in bivalves?
Bivalves with external fertilization are generally medium to large, which allows a large production of gametes that guarantee a high fertilization rate.
How do mollusks filter feed?
Mussels are filter feeders, which means they are like a small living pump. They draw in water from one side and they pump it out the other side, but in between they’ve got a massive rack of filters. And those filters work as gills, so they’re extracting oxygen out of the water but they’re also extracting food.
What is the ciliary feeder?
A method of feeding used by lancelets and many other aquatic invertebrates. The movement of cilia causes a current of water to be drawn towards and through the animal, and microorganisms in the water are filtered out by the cilia. From: ciliary feeding in A Dictionary of Biology »
Do mollusks eat zooplankton?
Mollusks eat a variety of organisms (see below). – Bivalves – A sub-group of mollusks that includes clams, mussels, scallops and oysters. Bivalves live on the ocean floor and feed on plankton (they are filter feeders). – Gastropods – A sub-group of mollusks, including snails, nudibranchs and abalone.
How do molluscs feed?
Feeding. Most molluscs are herbivorous, grazing on algae or filter feeders. Some feed on microscopic, filamentous algae, often using their radula as a ‘rake’ to comb up filaments from the sea floor. Others feed on macroscopic ‘plants’ such as kelp, rasping the plant surface with its radula.
What kind of food did the bivalve eat?
The primitive bivalve was almost certainly a detritivore (consumer of loose organic materials), and the modern palaeotaxodonts still pursue this mode of life. The posterior leaflike gills serve principally for respiration; feeding is carried out by the palp proboscides, which collect surface detritus.
What are the basic features of the bivalve?
General features. The bivalve body comprises a dorsal visceral mass and a ventral foot, which is enclosed within a thin mantle, or pallium. The mantle secretes from its outer surface a shell divided into left and right valves. Between the body and mantle is the mantle cavity, within which hang the left and right gills, or ctenidia.
How does a ctenidia get food into its mouth?
The ctenidia are incapable of filtering. The gut is minute, and detected prey is sucked into the mantle cavity by an inrush of water when the valves open. The food is then pushed into the mouth with the foot.