EVERYDAY SCIENCE

Detailed explanation-1: -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.

Detailed explanation-2: -All cnidarians are carnivorous predators. Jellyfish capture small drifting animals with their stinging cnidocyte-filled tentacles. Even the sessile coral polyps and sea anemones are predators ready to sting prey, grasp it in their tentacles, and push it into their mouth.

Detailed explanation-3: -Cnidarian predators use this exquisite mechanical device to capture and subdue prey. For the initial stage of prey capture, they generally rely on tentacles replete with nematocysts to interact with their prey. Tentacular nematocysts discharge in response to appropriate mechanical and chemical stimulation.

Detailed explanation-4: -Cnidarians contain specialized cells known as cnidocytes (“stinging cells”) containing organelles called nematocysts (stingers). These cells are present around the mouth and tentacles, and serve to immobilize prey with toxins contained within the cells.

Detailed explanation-5: -Cnidarians are carnivores, and some can also consume plant matter. They catch their food using their nematocysts or through filter feeding. Cnidarians digest their food using a primitive digestive system that contains no organs–they have a mouth (which also serves as the anus) and a gastrovascular cavity.