Just one, the mouth and anus in one. Food goes in and is taken up by the body, and waste comes out.
An opening
alot of people don't know!
a digestive system with a single opening
Cnidarians.
Yes; many cnidarians have an exoskeleton.
Most cnidarians have tentacles with stinging cells surrounding their mouth. The mouth is the only body opening. All cnidarianshave radial symmetry.
Cnidarians do not have legs. Many have stinging tentacles. The number of these varies by species.
A) Only one opening: they expel undigested material through the mouth.
Cnidarians do no possess eyes for sight, though many of them are able to sense light vs dark.
1
200
Mainly through suspension feeding. Cnidarians use stinging tentacles (nomocytes) to capture their prey. Once the tentacles grab the food it is absorbed in the gastrovascular cavity (stomach) and taken in asnutrients.