Cnidarians
Jellyfish, sea anemones, corals and the little freshwater hydra. Each has a soft body shaped like a sac with one opening, which takes food in and lets waste out, ringed by tentacles armed with stinging cells that catch small animals. Corals live in huge colonies and build hard cups of lime around themselves; over thousands of years these build coral reefs, home to a quarter of all sea species.
Depth 1 · Foundation
You can recognise a cnidarian by its sac-shaped body, its single opening and its stinging tentacles, and explain how corals build reefs.
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Foundation
You can recognise a cnidarian by its sac-shaped body, its single opening and its stinging tentacles, and explain how corals build reefs.
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