How does the cnidarian respiratory system work?

How does the cnidarian respiratory system work?

Respiration and excretion in cnidarians are carried on by individual cells that obtain their oxygen directly from water—either that in the coelenteron or that of the environment—and return metabolic wastes to it. Thus, all physiological functions are carried out at no more than the tissue level of differentiation.

Why don t cnidarians need a respiratory system?

Cnidarians are aquatic animals that contain stinging cells called cnidocytes. While cnidarians do not have lungs or other respiratory organs, they do use body cells to take in oxygen and expel waste gases. This can be a problem in areas with stagnant water, as the lack of circulation decreases the available oxygen.

Do Cnidaria have a circulatory system?

Cnidarians lack organs. This means that they do not have respiratory or circulatory systems. Like the cells in sponges, the cells in cnidarians get oxygen directly from the water surrounding them.

What do cnidarians breathe through?

Cnidaria have no organs like hearts or lungs. They have an internal cavity used for respiration and a gastrovascular cavity (a “stomach”) with a mouth but they do not have an anus. Other important functions like respiration and excretion occur by diffusion.

Do molluscs have a respiratory system?

Aquatic molluscs respire through ctenidia. These are the comb-like outgrowths of the mantle and are located within the mantle cavity.

Why do cnidarians have diffused nervous system?

Answer: Because pin the cnidarian body, the nerve net serves as a sensory locator neuron cell stretch all around the animals body and allow the cnidarian to detect chemical change ,to capture prey, and to move in response to stimulus.

Do cnidarians have a skeletal system?

Cnidarians have a hydrostatic skeleton. The contractile fibers act against the fluid-filled gastrovascular cavity. The movements are like a balloon; the animal can be short and thick or long and thin.

Do cnidarians have a reproductive system?

Reproduction of Cnidarians In general, polyps primarily reproduce asexually by budding, however, some produce gametes (eggs and sperm) and reproduce sexually. Medusae usually reproduce sexually using eggs and sperm. The planula then develops into a polyp that can reproduce either sexually or asexually.

Do mollusks have lungs?

Mollusk species that are exclusively aquatic have gills for respiration, whereas some terrestrial species have lungs for respiration. Additionally, a tongue-like organ called a radula, which bears chitinous tooth-like ornamentation, is present in many species, and serves to shred or scrape food.

What type of respiratory system does a cnidarian have?

Cnidaria A cnidarian neither needs nor possesses a respiratory system. The function of a respiratory system is to transport oxygen to an animal’s body cells in order to support cellular respiration, and to transport the poisonous CO2 produced as a waste product of cellular respiration out of the animal’s body.

What is the digestive system of cnidarians?

Cnidarians carry out extracellular digestion, where enzymes break down the food particles and cells lining the gastrovascular cavity absorb the nutrients. Cnidarians have an incomplete digestive system with only one opening; the gastrovascular cavity serves as both a mouth and an anus.

Do cnidarians have a complete digestive tract?

Like Porifera , Cnidaria lacks a complete digestive system, but does have a Gastrovascular Cavity (GVC). Extracellular digestion takes place within the central cavity. Like the Cnidarians, Platyhelminthes have a GVC, an incomplete digestive system.

What animals live in cnidarians?

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 .