1. Jellyfish, Sea anemones and Coral
Cnidarians
Jellyfish, Sea anemones and Coral

2. Cnidarians are soft-bodied, carnivorous animals that have stinging tentacles arranged in circles around their mouths.
Nematocyst – poison filled stinging structure that contains a tightly coiled dart.

3. Body Plans Cnidarians show radial symmetry
2 very different looking life stages
Polyp – sea anemone Medusa - Jellyfish

4. Life Processes
Feeding – carnivores, use nematocysts to capture….gastrovascular cavity – digestion chamber with one opening.
Respiration/circulation/excretion – diffusion
Response – nerve net – loosely organized network of nerve cells.
Movement
Polyps move by hydrostatic skeleton.
Medusa move by jet propulsion.

5. Asexual Reproduction
Asexual – Budding Swelling on polyp which falls off and produces more polyps.

6. Sexual Reproduction
Sexual – External fertilization – separate sexes – egg/sperm produce a larvae which turns into a polyp and the buds release medusa.

7. Types of Cnidarians 2. Hydra – a colony of separate organisms.
1. Jellyfish – largest is 4-6 meters
Ex. Portuguese man-of-war –tentacles can be 164 feet long

8. Types of Cnidarians
3. Sea anemones and Coral