EVERYDAY SCIENCE

Detailed explanation-1: -Anthozoans are long-lived, both individually and as colonies; some sea anemones are centuries old. All medusae and sea anemones occur only as solitary individuals. Scyphomedusae can weigh more than a ton, whereas hydromedusae are, at most, a few centimetres across.

Detailed explanation-2: -Many anthozoans are colonial and consist of multiple polyps with a common origin joined together by living material.

Detailed explanation-3: -Anthozoans are probably the most famous cnidarians: they include the corals that build great reefs in tropical waters, as well as sea anemones, sea fans, and sea pens.

Detailed explanation-4: -Within the phylum Cnidaria, the class Anthozoa includes corals, anemones, sea pens and seafans. Anthozoa consists of 10 orders and thousands of species. Adults are attached to the seabed, but their larvae are free-floating and can drift to new settlements.

Detailed explanation-5: -Unlike other cnidarians, anthozoans do not have a medusa stage in their development, they live exclusively as polyps throughout their life cycles. Instead, they release sperm and eggs that form a planula, which attaches to some substrate on which the cnidarian grows.