Incurrent and excurrent siphons are the tubular structures that burrowing bivalve molluscs, such as clams, use to feed, respire, reproduce and expel waste into the water, while the body of the bivalve remains buried beneath the surface of the sediment, where it is hidden from predators.
The bivalve's two siphons are situated at the posterior edge of the mantle cavity. There is an inhalant or incurrent siphon, and an exhalant or excurrent siphon. The water is circulated by the action of the gills. Usually water enters the mantle cavity through the inhalant siphon, moves over the gills, and leaves through the exhalant siphon.
The mantle of the two sides comes together at the posterior end of the clam to form the incurrent and excurrent siphons. Clams filter water for feeding and breathing. The leaf-like gills are just internal to the mantle on both sides of the body. Remove a gill, cut across it, and examine it with the dissecting microscope; what evidence do you ...
A tunicate is a marine invertebrate animal, a member of the subphylum Tunicata. It is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords. The subphylum was at one time called Urochordata, and the term urochordates is still sometimes used for these animals.
Excurrent and Incurrent Siphons Beating cilia of gills causing water to enter the mantle cavity through incurrent siphons and out the ex-current siphons. Foot Muscular/adapted for locomotion, attachment, and food capture. Palps Secretes a mucus that entangles suspended food and nutrient particles within the water to produce a ball of food and mucus called a bolus.
Generally the bivalves are filter feeders. As you look at a bivalve in the water and undisturbed one will see a slight protrusion of its siphons (incurrent and excurrent).
The clam has two siphons. The excurrent siphon (which expels water and waste out of the clam) and the incurrent siphon (which brings oxygen and food and water into the clam).
clam dissection. STUDY. PLAY. what controls the opening and closing of the calm valves. the adductor muscle. ... what are the function of the incurrent and excurrent siphons. incurrent brings in oxygen food and water and the excurrent exits water and wastes. what are the two functions of the gills in the clam.
What does the phylum Mollusca include? It includes animals such as clams, mussels, scallops, snails, slugs, squids, and octopuses. ... The incurrent and excurrent siphons. What are these two shells? ... Into the water in the excurrent siphon just before it exits the clam.
13. Locate two openings on the posterior end of the clam. The more ventral opening is the incurrent siphon that carries water into the clam and the more dorsal opening is the excurrent siphon where wastes & water leave. The large muscle attached to the siphons is called the siphon retractor muscle. There would be another one on the right side.