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How do mollusks remove nitrogenous waste?
- Mollusks have a kidney located near the heart. They use this to remove nitrogenous waste from the "blood," it is then carried via the excretory duct, which runs alongside the rectum to a pore located at the mantle edge.
What kind of excretory organ do molluscs have?
Complete answer: The excretory organs of Mollusca are metanephridia. A molluscan body is found to be unsegmented. However, they do have a distinct head, a muscular foot, and a visceral hump.
What secretes the shell of a mollusk?
A mantle, a highly modified epidermis that covers and protects the soft body. In most species, the mantle also secretes a shell of calcium carbonate.
How do mollusks exchange gases?
Molluscs have gills in their mantle cavity, which are used for respiration to exchange oxygen and carbon dioxide. Gills are employed by some bivalves for both filter feeding and breathing. Land molluscs have pulmonary sacs or cavities, which are aerial respiration organs.
Do mollusks excrete ammonia?
The vast majority of mollusks are aquatic and excrete nitrogen in the form of ammonia.
How does excretion take place in snails?
Land snails excrete the undigested parts of their food from the anal pore, located in the mantle, at the edge of the shell in shelled species. Snail excrement may appear as a tiny folded rope.
Do mollusks shed their shells?
Since their exoskeleton is not shed, molluscan shells must enlarge to accommodate body growth. This pattern of growth results in three distinct shell layers: an outer proteinaceous periosteum (uncalcified), a prismatic layer (calcified) and an inner pearly layer of nacre (calcified).
What is a mollusk without a shell called?
Among the shell-less molluscs ("Aplacophora") there are about 340 of the most primordial molluscs to be found on earth. As their scientific name Aplacophora literally states, the members of this group actually are devoid of a shell and in that regard are unique among molluscs.
Which of the following structure helps in excretion and respiration in molluscs?
These gills have respiratory and excretory functions.
What are 3 facts about mollusks?
Fast Facts: MollusksScientific Name: Mollusca (Caudofoveates, Solanogastres, Chitons, Monoplacophorans, Scaphopods, Bivalves, Gastropods, Cephalopods)Common Name: Mollusks or molluscs.Basic Animal Group: Invertebrate.Size: Microscopic to 45 feet in length.Weight: Up to 1,650 pounds.More items...•
How do molluscs obtain oxygen?
Basically all molluscs breathe by gills that are called ctenidia (comb-gills) because of their comb-like shape. In terrestrial molluscs this respiration organ is reduced, but still respiration takes place in the pallial cavity. That is why it is also called the snail's respiratory cavity.
How do mollusks digest food?
The food is taken up by cells lining the digestive glands arising from the stomach, and then to the intestine from where it is passed into the blood whereas, undigested materials are compressed and packaged before it is discharged through the anus into the mantle cavity.
What is the excretory organ of bivalves?
The excretory organs of bivalves are a pair of nephridia. Each of these consists of a long, looped, glandular tube, which opens into the pericardium, and a bladder to store urine.
What type of circulatory system do molluscs have?
Mollusks possess an open circulatory system in which body fluid (hemolymph) is transported largely within sinuses devoid of distinct epithelial walls.
What are the excretory organs in arthropods?
Excretory organs of arthropods are either green glands or malpighian tubules. In some forms, coxal glands are excretory organs.Annelids have nephridia as an excretory organ.So, the correct answer is option B.
What type of body cavity do molluscs have?
EXPLANATION: The main body cavity of mollusks is a haemocoel, through which blood circulates. The mollusks are triploblastic organisms with true coelom.
Mollusca
The Phylum Mollusca consists of approximately 85,000 different species. The organisms that make up the phylum are invertebrates.The work Mollusca derives from the Latin word mollis which means "soft" or "flexible." The Mollusca excretory process involves a the organ of the kidney. This organ filters waste from the organism from the blood.
Garden Snails ( Cornu aspersum)
Snails, along with all gastropods and many mollusks, have an excretory organ called the nephidrium. The organ is necessary to maintain fluid balance within snails. Water, minerals, and other substances go through the nephidrium to filter the It is a long coiled Another vital part of the snail's excretory anatomy is the haemolymph, or heart sac.
Clam (mercenaria Mercenaria)
The clam, similarly to Snails, also have a nephidrium. Funnel-like tubes filters the blood of the clam, ridding of all toxins and excess water. The clam, along with this, have two kidneys that move waste from the pericardial to mantle cavity. The waste from the mantle cavity has its wasted washed away by water.
Squid ( Loligo Duvaucelii)
The squid has two kidneys, this cleans the blood of any excesses within it. This kidney is located rather closely to the heart. Then these kidneys are extended through to the liver, where it eventually is excreted in the funnel, which is a tube located behind the head of the squid.
