A) Only one opening: they expel undigested material through the mouth.
Cnidarians have no gut in their body .The structure which performs function similar to gut is called gastrovascular cavity .
No ,they lack gut but possess gastrovascular cavity .
A bilateral animal has a lined gut cavity. On the other hand, animals like roundworms have a gut cavity but it is only partially lined.
A complete gut allows for unidirectional movement of food through specialized regions like the stomach and intestines, aiding in digestion and absorption of nutrients more efficiently. In comparison, a gastrovascular cavity has a single opening for both ingestion and excretion, limiting the ability to digest food as thoroughly. This makes a complete gut more efficient for nutrient acquisition and waste removal in more complex organisms.
That is not accurate. Cnidarians actually have a simple coelom called a gastrovascular cavity, which functions in digestion and circulation. Sponges, on the other hand, lack a true coelom and instead have a porous body filled with channels for water circulation.
Acoelomates, such as flatworms, do not have a true gut cavity; instead, they possess a gastrovascular cavity that functions in both digestion and nutrient distribution. This cavity is more sac-like compared to the complete digestive systems found in coelomates, but it has a single opening that serves as both mouth and anus. Overall, the digestive system in acoelomates is simpler and less specialized than in organisms with coelomic cavities.
Cnidarians are also called Coelenterates because they possess a central cavity or coelenteron that serves various functions, including digestion and waste removal. This cavity is a defining feature of this group of animals and gives them their alternate name.
No. Porifera and Cnidarians lack a through gut.
Some chordates have them, and in some the distinction may need to be qualified. In molluscs they remain undifferentiated, in mammals for example they differentiate into separate cavities, the pleural, peritoneal and pericardial.
The characteristic that gives cnidarians their name is: cnidarian means "nettle" and nettles are plants that release stinging barbs into the skin. All cnidarians have stinging cell's. Cnidarians have complex tissues, a gut for digesting food, and a nervous system.
The gastroderm is the inner layer of cells that lines the gut or digestive cavity of cnidarians such as jellyfish and corals. It is involved in digestion, absorption of nutrients, and in some cases, defense mechanisms.
A gut is the internal digestive tract of an organism, while a body cavity is a fluid-filled space within the body that contains and protects organs. The gut is a specific organ system responsible for digestion, while body cavities serve a more general protective function.