1. Phylum Cnidaria
Cnidarians Include Hydras, jellyfish, sea anemones & corals
Radially symmetrical
Acoelomate
Two basic forms:
Polyp: Cylindrical form which attach bases to substratum
Medusa: Flattened, mouth down version of the polyp. Moves freely

2. Forms of Cnidarians

3. Body Plan Basic Body Plan: Has an outer epidermis
Has an inner gastrodermis which forms a gastrovascular cavity
Has a middle "jelly filled" layer called mesoglea

4. Cnidocytes
Cnidarians are predators which have tentacles possessing batteries of special cells called Cnidocytes
Cnidocytes contain special stining capsules called nematocysts.
When triggered, these cells shoot out a discharge thread which can entangle and/or poison it's intended prey

6. Reproduction 3 Major classes
Reproduction can occur sexually by fertilization of egg and sperm forming larvae.
Reproduction can also occur asexually through budding
3 Major classes
Class Hydrozoa: Hydras
Class Scyphozoa: Jellyfish
Class Anthozoa: Anemones and corals

7. Class Hydrozoa: The Hydras
Polyp phase is dominant
Generally microscopic
Generally freshwater

8. Class Scyphozoa: The Jellies
Generally refered tro as jellies
Medusa stage is dominant
Come in a variety of forms
Aggressive predators, and can be dangerous to humans
Jelly
Portugese
Man-o-war

9. Class Anthozoa: Anemones & Corals
Appear like plants but are animals.
Polyp form is dominant.
Corals build calcium shells to protect themselves
Have symbiotic relationship with algae.
Can build extensive masses which can form land masses.
Anemone
Coral Polyps

10. Coral Reefs
Clownfish living in
An anemone