AP BIOLOGY

Detailed explanation-1: -Cnidarians exhibit a specific characteristic – tentacles with stinging nematocytes which serve as small harpoons which react to stimuli by giving out tiny stinging cells which can poison and hook potential prey. Cnidarians do not show bones and a central nervous system, rather have a nerve net.

Detailed explanation-2: -Cnidarians have a unique feature: stinging cells called cnidocytes (NID-uh-sites). Each cnidocyte cell has a long, coiled, tubular harpoon-like structure, called a nematocyst (Greek root word nema meaning thread; Greek root word cyst meaning bag).

Detailed explanation-3: -The cnidocytes – or stinging cells – that are characteristic of sea anemones, hydrae, corals and jellyfish, and make us careful of our feet while wading in the ocean, are also an excellent model for understanding the emergence of new cell types, according to new Cornell research.

Detailed explanation-4: -All Cnidaria are aquatic, mostly marine, organisms. They all have tentacles with stinging cells called nematocysts that they use to capture food. Cnidarians only have two body layers, the ectoderm and endoderm, separated by a jelly-like layer called the mesoglea. Most Cnidarians have radial symmetry.