1. Sponges and Cnidarians
Chapter 33

2. Phylum Porifera-“pore-bearers”
NO organs or body systems
Asymmetry
All are SESSILE; they do not move
Sponges are filter–feeders because they cannot search for food.
They have 2 cell layers.
Body structure resembles a hollow cylinder that is closed at the bottom and has an opening at the top called an OSCULUM.

3. Sponge structure
Pores called OSTIA allow food and oxygen to enter the body.
The inner layer is lined with flagellated collar cells called CHOANOCYTES. The beating of the flagella causes water to circulate into the sponge through its pores.
AMOEBOCYTES- cells that can move around the sponge’s body carrying nutrients to other cells,

7. ASEXUALLY REPRODUCTION
SIMPLE SKELETON:
SPONGIN-soft
SPICULES-hard
ASEXUALLY REPRODUCTION
budding
regeneration
SEXUAL REPRODUCTION
Some are hermaphrodites-produce egg and sperm
They can not self-fertilize.

8. Phylum CNIDARIANS (COELENTERATES= HOLLOW GUT)
Jellyfish, hydra, coral, sea anemone, Portuguese man of war
Tentacles have cnidocytes or stinging cells which help them paralyze and capture prey; also aid in protection
When tentacles touch a food source a nematocyst shoots out to paralyze prey
RADIAL symmetry
Two layers of cells

9. Gastrovascular cavity -stomach for food digestion
No head or brain
Nerve net allow them to respond to the environment
Two body forms
POLYP-vase shape (sea anemone)
MEDUSA- bell shape (JELLYFISH)

10. CLASS HYDROZOA PORTUGUESE MAN-OF-WAR HYDRA-live in freshwater
Consist of a colony of animals working together
Stings are extremely painful.
HYDRA-live in freshwater

11. CLASS CUBOZOA
Also known as box jellies for their cube shaped medusa

12. CLASS SCYPHOZOA
Cup animals-jellyfish

13. Jellyfish life cycle

14. CLASS ANTHOZOA “flower animal”
Sea anemone
Mutualistic relationship with the clownfish
Food and protection
Coral
Polyps die and leave hardened shells
Coral reefs provide food and shelter for marine animals
Mutualistic relationship with algae
Algae produces food
Coral provides protection and access to light

15. PowerPoints/Booklets Due May