Do Cnidaria have a mantle?

Do Cnidaria have a mantle?

Mollusks also have a thin layer of tissue called a mantle that covers its internal organs and its main organ called a foot. Cnidarians (ny DEHR ee unz) are invertebrates that have stinging cells and take food into a central body cavity. Cnidarians use sting cells to capture food and defend themselves.

What do all Cnidaria have in common?

Cnidarians share several basic characteristics. All Cnidaria are aquatic, mostly marine, organisms. They all have tentacles with stinging cells called nematocysts that they use to capture food. Cnidarians only have two body layers, the ectoderm and endoderm, separated by a jelly-like layer called the mesoglea.

Which of the following are characteristics of cnidarians?

They are mostly marine animals which includes organisms like sea anemone, corals, hydras, jellyfish, etc. Cnidarians are diplobalstic, i.e., they have only two germ layers – endoderm and ectoderm. They are acoelomates – body cavity is absent. Their body shows radially symmetry.

How many species of cnidaria are there?

9,000
cnidarian, also called coelenterate, any member of the phylum Cnidaria (Coelenterata), a group made up of more than 9,000 living species.

Do cnidarians have appendages?

Arthropodainvertebrate phylum of animals characterized by a segmented body, jointed appendages, exoskeleton, and brain. Cnidariaaquatic invertebrate phylum that includes animals such as jellyfish and corals that are characterized by radial symmetry and tissues, and a stinger called a nematocyst.

Do all cnidarians have tentacles?

All Cnidarians have tentacles with stinging cells in their tips which are used to capture and subdue prey. In fact, the phylum name “Cnidarian” literally means “stinging creature.” The stinging cells are called cnidocytes and contain a structure called a nematocyst. The nematocyst is a coiled thread-like stinger.

Do all cnidarians have radial symmetry?

All cnidarians have a central point or axis, and if you divide a cnidarian through this central axis, you’ll end up with equal parts on either side. Even though cnidarians vary a great deal, they all have radial symmetry as a common characteristic.

Are all cnidarians carnivores?

All cnidarians are carnivores. Most use their cnidae and associated toxin to capture food, although none is known actually to pursue prey. Sessile polyps depend for food on organisms that come into contact with their tentacles.

Do cnidarians have Cephalization?

Cnidarians are radially symmetrical (i.e., similar parts are arranged symmetrically around a central axis). They lack cephalization (concentration of sensory organs in a head), their bodies have two cell layers rather than the three of so-called higher animals, and the saclike coelenteron has one opening (the mouth).