Phylum Cnidaria
Cnidarians are a diverse group of animals found in marine environments. They are characterized by the presence of specialized cells called cnidocytes, which contain stinging structures known as nematocysts.

Key Characteristics of Cnidarians
- Radial symmetry: Cnidarians exhibit radial symmetry, with body parts arranged around a central axis.
- Two body forms: Cnidarians can exist in two body forms - polyps and medusae.
- Nematocysts: Specialized stinging cells called cnidocytes help cnidarians capture prey and defend themselves.

Major Classes of Cnidarians
- Class Hydrozoa: Includes colonial animals like Portuguese man o' war and hydras.
- Class Scyphozoa: Includes true jellyfish.
- Class Anthozoa: Includes sea anemones and corals.

Ecological Importance
- Cnidarians play a crucial role in marine ecosystems as both predators and prey.
- Coral reefs, formed by the calcium carbonate skeletons of corals, are among the most diverse ecosystems on Earth.

Relation to Animal Kingdom
- Cnidarians belong to the animal kingdom, specifically invertebrates.
- They share common characteristics with other animal phyla, such as multicellularity and heterotrophic mode of nutrition.
In conclusion, the phylum Cnidaria is a diverse group of marine animals with unique characteristics like radial symmetry, nematocysts, and two body forms. They play a significant ecological role in marine ecosystems and are an important part of the animal kingdom.

Phyllum mai cnidaria hai ?