Is Mollusca acoelomate or Coelomate?

Yes, molluscs have developed a true coelom. They are bilaterally symmetric and triploblastic. The coelom is an internal body cavity bound by mesodermal membranes.

Is phylum Mollusca acoelomate?

Molluscs had a common origin with the annelids, as shown by remarkable ontogenetic similarities. Their common ancestors were non-segmented (non-eumetameric), acoelomate animals.

Are animals in Mollusca Coelomate Pseudocoelomate or acoelomate?

Animals in the phylum Mollusca include clams, snails, octopuses, and sea slugs (pictured right). They are all protostome coelomates.

What type of phylum is Mollusca?

Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (/ˈmɒləsk/). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species.

Is Mollusca a Pseudocoelomate?

Type of Coelom: Animals in Mollusca are coelomates. Examples of phylum Mollusca are Sea Hares, Sea Butterfly, Squid, Octopus, and cuttlefish. So, the correct answer is ‘Nematoda’.

What are acoelomate animals?

Definition of acoelomate : an invertebrate lacking a coelom especially : one belonging to the group comprising the flatworms and nemerteans and characterized by bilateral symmetry and a digestive cavity that is the only internal cavity.

Is Mollusca a pseudocoelomate?

What phylum is acoelomate?

phylum Platyhelminthes
Acoelomate Examples Examples of acoelomates are found in the kingdom Animalia and the phylum Platyhelminthes. Commonly known as flatworms, these invertebrate animals are unsegmented worms with bilateral symmetry.

Are animals in Cnidaria Platyhelminthes and Mollusca coelomate pseudocoelomate or acoelomate?

Acoelomates. Acoelomate animals are called acoelomates and they have no true body cavity. The acoelomate phyla are Placozoa, Porifera, Cnidaria, Ctenophora, Platyhelminthes, Mesozoa, Nemertina, Gnathostomulida.

What is phylum Mollusca characteristics?

The animals belonging to the phylum Mollusca have soft-bodies, triploblastic and bilaterally symmetrical and coelomate. The study of Mollusca is called Malacology. They are sluggish invertebrates, with a thin fleshy envelope or mantle covering the visceral organs.

How do you identify Mollusca?

Characteristic Features of Phylum Mollusca

1. They are bilaterally symmetrical.
2. They are triploblastic, which three layers.
3. They show organ system grade of organisation.
4. The body is soft and unsegmented.
5. Body is divisible into three regions – head, a visceral mass, and ventral foot.
6. Body is covered by a mantle and shell.

Which phylum has a pseudocoelom?

phylum Aschelminthes
Pseudocoelom or false coelom is found in the phylum Aschelminthes.

How do mollusks respire?

Terrestrial mollusks exchange gases with the surrounding air. This occurs across the lining of the mantle cavity. Aquatic mollusks “breathe” under water with gills. Gills are thin filaments that absorb gases and exchange them between the blood and surrounding water.

Why do molluscs and arthropods have reduced coelom?

The body cavity or the coelom of arthropods and molluscs is filled with blood. The haemocoel is an enlarged blastocoel, which greatly reduces the coelom (this is restricted to the cavities of the gonads and excretory organs). The haemocoel can act as a hydrostatic skeleton.

What animals are coelomates?

The protostome coelomates (acoelomates and pseudocoelomates are also protostomes) include the mollusks, annelids, arthropods, pogonophorans, apometamerans, tardigrades, onychophorans, phoronids, brachiopods, and bryozoans. Deuterostomes include the chaetognaths, echinoderms, hemichordates, and chordates.

What is coelomate and acoelomate?

Description. Coelomates are organisms with a fluid-filled cavity between the gut wall and the outer body wall. An acoelomate is an organism that does not contain a fluid-filled cavity in their bodies.

Are mollusks pseudocoelomates?

The protostome coelomates (acoelomates and pseudocoelomates are also protostomes) include the mollusks, annelids, arthropods, pogonophorans, apometamerans, tardigrades, onychophorans, phoronids, brachiopods, and bryozoans.

Which phyla are considered acoelomates?

The three phyla considered in this chapter are the Platyhelminthes or flatworms; the Nemertea or ribbon worms; and the Gnathostomulida or jaw worms.

What is the main characteristic that all Mollusca have in common?

Molluscs are a clade of organisms that all have soft bodies which typically have a “head” and a “foot” region. Often their bodies are covered by a hard exoskeleton, as in the shells of snails and clams or the plates of chitons.