What are hollow sac like animals?

Cnidaria/Coelenterata (Hollow sac-like Animals)

What are the four main features of phylum Coelenterata?

The body is radially symmetrical. The digestion is both intracellular and extracellular. The nervous system and the circulatory system is absent….Scyphozoa

• They are found exclusively in the marine environment.
• Medusa is dominant and umbrella-shaped.
• Polyps are not present.
• Mesogloea is cellular.

What are the salient features of phylum Coelenterata?

Characteristics. All coelenterates are aquatic, mostly marine, animals. The body form is radially symmetrical, diploblastic and does not have a coelom. The body has a single opening, the hypostome, surrounded by sensory tentacles equipped with either nematocysts or colloblasts to capture mostly planktonic prey.

Are coelenterates segmented?

> Option C- Coelenterata: Most of the coelenterates are aquatic. They are diploblastic, radially symmetrical and lack coelom. They have radial symmetry and are unsegmented.

Is Coelenterata and Cnidaria same?

cnidarian, also called coelenterate, any member of the phylum Cnidaria (Coelenterata), a group made up of more than 9,000 living species. Mostly marine animals, the cnidarians include the corals, hydras, jellyfish, Portuguese men-of-war, sea anemones, sea pens, sea whips, and sea fans.

How are cnidarians classified?

Cnidarians are classified into four main groups: non-moving (sessile) Anthozoa (sea anemones, corals, sea pens); Cubozoa (box jellies);swimming Scyphozoa (jellyfish); and Hydrozoa, a broad group that includes all the freshwater cnidarians as well as many marine forms. Cnidaria have no organs like hearts or lungs.

Why coelenterates are called diploblastic animals True or false?

Explanation: Coelenterates having two embryonic layers i.e., ectoderm and endoderm having undifferentiated mesoglea between two layers. Hence, coelenterates are called diploblastic animals. Coelenterates are diploblastic animals because it consists of two embryonic layers.

How do Poriferan animals differ from Coelenterate animals?

The body of Porifera is made up of a single layer of cells. The body of Coelenterate is made up of two layers of cells. Example : Spongilla, Euplectella, etc. Example : Hydra, sea anemone, corals, etc.

Why Coelenterates are called Diploblastic animals?

The body of coelenterates have two cell layers with an outer ectoderm, and an inner endoderm. Thus they are called diploblastic animals.

How do cnidarians differ from all other animals?

Cnidarians are distinguished from all other animals by having cnidocytes that fire harpoon like structures and are usually used mainly to capture prey. In some species, cnidocytes can also be used as anchors.

Which of the following animals belong to 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. The phylum Cnidaria is made up of four classes: Hydrozoa (hydrozoans); Scyphozoa (scyphozoans); Anthozoa (anthozoans); and Cubozoa (cubozoans).