28.2: Phylum Cnidaria - Biology LibreTexts

11.5: Cnidarians - Biology LibreTexts

Cnidarians are aquatic invertebrates with tissues and radial symmetry. They have tentacles with stingers called nematocysts. They have two body plans: polyps and medusae, which may alternate or exist in different species.

ADW: Cnidaria: INFORMATION

Cnidaria is a phylum of radially or biradially symmetric animals with two or three layers of tissues. They have a gastrovascular cavity, tentacles, and nematocysts, and include jellyfish, corals, and sea anemones.

Cnidaria - Wikipedia

Many species of Cnidaria may spawn simultaneously in the same location, so that there are too many ova and sperm for predators to eat more than a tiny percentage — one famous example is the Great Barrier Reef, where at least …

Phylum Cnidaria | Characteristics, Symmetry

Nov 21, 2023 · Cnidarians exhibit radial symmetry, which means that they are split into identical pieces along a central axis. The cnidarian life cycle has two distinct morphological forms: polyploid and...

Cnidaria - Digital Atlas of Ancient Life

Learn about the diversity, features, and evolution of cnidarians, a phylum of aquatic animals with radial symmetry and cnidae. Explore the fossil record of corals, sea anemones, jellyfish, and other cnidarians.

A Guide to the Cnidarians: Basics and Beyond

Mar 30, 2019 · Additionally, two groups of cnidarians, corals and sea anemones, exhibit six- or eight-fold symmetry. These types of symmetry are referred to as hexamerism and octamerism, respectively. It should be noted that cnidarians …

Characteristics of Phylum Cnidaria | Biology for …

Cnidaria is a phylum of animals with two body plans, polyp and medusa, that exhibit radial or biradial symmetry and have stinging cells called cnidocytes. Learn about their life cycle, cellular structure, and diversity of forms and habitats.