What is the body structure of cnidarians?
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What is the body structure of cnidarians?
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).
What is the body structure of sponges?
A sponge’s body is hollow and is held in shape by the mesohyl, a jelly-like substance made mainly of collagen and reinforced by a dense network of fibers also made of collagen. The inner surface is covered with choanocytes, cells with cylindrical or conical collars surrounding one flagellum per choanocyte.
How are sponges and cnidarians alike?
Porifera and Cnidaria are organisms which share similar characteristics with one another. -They are both multicellular, they consist of many cells working together. They are both eukaryotic, they have DNA in the form of chromosomes contained within a distinct nucleus.
Which characteristic do sponges and cnidarians share?
The characteristic shared by all of these species is that their gonads are derived from epidermal tissue, whereas in all other cnidarians, they are derived from gastrodermal tissue (Figure 15.2.
Is a sponge a cnidarian?
Sponges belong to Phylum Porifera. Cnidarians belong to Phylum Cnidaria.
What type of body cavity does Cnidaria have?
The body cavity (gastrovascular cavity) is sac-shaped, with one opening acting as both mouth and anus. This opening is surrounded by tentacles bearing thread cells. Cnidarians exist both as free-swimming medusae (e.g. jellyfish) and as sedentary polyps.
What are the structural cells of sponge?
Specialised Cells: Sponges have special collar cells (or choanocytes) that are unique in the animal kingdom. They have flagella, whip-like structures that work to set up water currents so the sponge can sieve food particles from the water.
What are the three sponge body forms?
Most sponges fall into one of three categories, based on their canal systems – asconoid, syconoid and leuconoid.
How do body of cnidarians differ from sponges?
Sponges vs Cnidarians One interesting difference between sponges and cnidarians is that sponges lack tissue while cnidarians have tissues but not the organ systems. Sponges and Cnidarians are very primitive acoelomic invertebrates with very simple body structures. Both organisms are found in aquatic ecosystems.
How does the body plan of cnidarians differ from sponges?
Sponges have multiple cell types that are geared toward executing various metabolic functions. Cnidarians have outer and inner tissue layers sandwiching a noncellular mesoglea. Cnidarians possess a well-formed digestive system and carry out extracellular digestion.
How is Cnidaria different to porifera?
Cnidaria and porifera are two different phyla. Cnidarians have Cnidocytes but not the poriferans. Cnidarians have well-organized organ systems but not the poriferans; on the other hand, poriferans have an efficient tunnel system made up of pores but not the cnidarians.
Which body plan of cnidarians is more similar to that of a sponge?
How is the body plan of a cnidarian similar to that of a sponge? They are both soft bodied animals with a hollow central cavity.
Whats the difference between sponges and cnidarians?
What is the body cavity of sponges?
spongocoel
A spongocoel (/ˈspɒŋɡoʊˌsiːl/), also called paragaster (or paragastric cavity), is the large, central cavity of sponges. Water enters the spongocoel through hundreds of tiny pores (ostia) and exits through the larger opening (osculum).
What type of body cavity do sponges have?
Simple sponges of the asconoid type have a small central cavity or spongocoel, where the choanocytes are located. The more complex syconoid sponges (like Grantia) have folded canals of feeding cells off the spongocoel.
What is the name of the body cavity of a sponge?
The body of the simplest sponges takes the shape of a cylinder with a large central cavity, the spongocoel. Water enters the spongocoel from numerous pores in the body wall. Water flows out through a large opening called the osculum ([Figure 2]).
What is the skeleton of a sponge made of?
Sponge skeletons are made of rod-like silica structures called spicules that are cemented to rocks and to each other with collagen.
What is the skeleton of a sponge?
