Molluscs have no true tissues and are filter feeders, while cnidarians have true tissues and a gastrovascular cavity.

What are the unique features of Mollusca?

Characteristic Features of Phylum Mollusca

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

Are Mollusca symmetrical?

The generalized mollusc is bilaterally symmetrical and has a single, "limpet-like" shell on top. The shell is secreted by a mantle covering the upper surface. The underside consists of a single muscular "foot".

What characteristics of Mollusca distinguish it from other phyla?

Mollusks all have a mantle, a shell secreted by the mantle, a visceral hump, a foot, and a radula. Mollusks are different from other phyla because they have these things, most of which are unique to the phylum Mollusca. Describe the valve of a clam. The valve of a clam is also known as each half of the clam's shell.

How many embryonic layers are present in phylum Mollusca?

Mollusks are triploblasts meaning that they develop from three basic embryonic germ layers: an endoderm, a mesoderm, and an ectoderm.

Mollusca | Gastropods-Bivalves-Cephlapods |

43 related questions found

Do all molluscs have shells?

You are probably familiar with a number of mollusks: they include the snails, octopuses, squids, clams, mussels, scallops, oysters, and chitons, among others. ... Though there are qualities that all mollusks share, you may be surprised to learn that not all of them have shells.

Which of the following animal belongs to phylum Mollusca?

The animals belonging to the phylum Mollusca are apple snail, pearl oyster, devil fish, tusk shell, etc.

Which is true about Mollusca?

Mollusca have bilateral symmetry and they have CaCO₃ (calcareous) shell.

What are 2 differences in phylum Mollusca and phylum echinodermata?

The key difference between Mollusca and Echinodermata is the habitat they live in. Molluscs live in both terrestrial and aquatic environments. In contrast, echinoderms only live in marine environments. ... Clams, oyster and squid, are some molluscs while sea cucumber, starfish and sea urchin are some echinoderms.

Which of these class is phylum Mollusca?

The Phylum Mollusca consist of 8 classes: 1) the Monoplacophora discovered in 1977; 2) the worm-like Aplacophora or solenogasters of the deep sea; 3) the also worm-like Caudofoveata; 4) the Polyplacophora, or chitons; 5) the Pelecypoda or bivalves; 6) the Gastropoda or snails; 7) the Scaphopoda, or tusk shells; and 8) ...

Does Mollusca have exoskeleton?

Molluscs are mostly aquatic, and are named from the Latin molluscus, meaning "soft". Their soft bodies are enclosed in a hard shell made of calcium carbonate (CaCO3), which functions as an exoskeleton. This shell is secreted by a thin sheet of tissue called the mantle, which encloses the internal organs like a glove.

Are molluscs vertebrates or invertebrates?

mollusk, also spelled mollusc, any soft-bodied invertebrate of the phylum Mollusca, usually wholly or partly enclosed in a calcium carbonate shell secreted by a soft mantle covering the body.

What type of symmetry is Mollusca?

Mollusks have bilateral symmetry. – The two halves of the body mirror each other. Gastropods (snails) ~ eat with a radula (tiny tongue covered with teeth.

Is Mollusca a direct or indirect development?

15. Development:

They are oviparous. The development is either direct or indirect (metamorphosis). When the development is indirect it includes a characteristic larva, liger, trochophore or glochidium.

Is Mollusca oviparous or viviparous?

Birds, reptiles, amphibians, most fish, insects, mollusks, arachnids, and monotremes are oviparous animals. Most mammals are viviparous animals.

Are Mollusca Monoecious or dioecious?

Molluscs are either dioecious, with separate sexes, or hermaphroditic, one individual bearing both male and female sex organs. The eggs of aquatic species of bivalves and some species of gastropods develop into trochophores, which in turn usually develop into veliger larvae.

What are the differences between Mollusca and echinodermata?

Mollusks have soft bodies, and most secrete a shell to protect it. ... Echinoderms don't have shells, but they have other means of protection. Their name comes from the Greek words for "spiny skin," and many echinoderms such as sea urchins have long spines growing from their bodies.

What type of organisms belong to phylum echinodermata and phylum Mollusca?

shellfish, any aquatic invertebrate animal having a shell and belonging to the phylum Mollusca, the class Crustacea (phylum Arthropoda), or the phylum Echinodermata. The term is often used for the edible species of the groups, especially those that are fished or raised commercially.

Which of the following is true about reproduction in Mollusca?

The simplest species of molluscan reproductive system relies on external fertilization. ... Some species of mollusc are hermaphrodites that reproduce by internal fertilization. Therefore, option C both sexual and asexual reproduction is the correct answer. So, option C is the correct option.

In which Mollusca of the following internal shell is present?

Cuttlefish, squid, spirula, vampire squid, and cirrate octopuses have small internal shells.

Is the second largest phylum in animal kingdom?

Complete answer: Mollusca is the second largest Phylum in the Animal Kingdom. Molluscs are both terrestrial and aquatic (marine or freshwater).

Which of the following animals does not belong to phylum Mollusca?

Trematoda do not belong to phylum Mollusca It is a class of phylum Platyhelminthes.

Which of the following animals belong to the phylum Cnidaria?

Mostly marine animals, the cnidarians include the corals, hydras, jellyfish, Portuguese men-of-war, sea anemones, sea pens, sea whips, and sea fans.

Is a snail a mollusk?

The Class Gastropoda (in Phylum Mollusca) includes the groups pertaining to snails and slugs. The majority of gastropods have a single, usually spirally, coiled shell into which the body can be withdrawn.