1. Sponges and Cnidarians
4/14/15
Mr.Faia
6th Grade Science

2. Sponges For a long time, sponges were thought of as plants
Sponges stay in 1 place, but are heterotrophs
They have been
around for 540 million years!

3. Sponges Sponges have irregular shapes and no symmetry
Some cells have specialized jobs

4. Structure of a Sponge
The body of a sponge is like a bag pierced with holes
These holes are called pores

5. Getting Food and Oxygen from Water
Sponges strain food from water
Collar cells trap food as water passes through

6. Getting Food and Oxygen from Water
Oxygen enters the sponge by diffusion
What is diffusion?
What else can diffusion do for a sponge?

7. Spikes Sponge bodies are supported by spikes Spikes can be very sharp
Sponges can also produce irritating substances
What do we call these traits?

8. Reproduction
Can reproduce both sexually and asexually
Budding –

9. Reproduction Produce egg cells during 1 point of year
Produce sperm cells during another point
After fertilization, a larva forms

10. Cnidarians
3 Members of the phylum
Jellyfish
Sea Anemones
Corals

11. Cnidarians Traits Stinging Cells Hollow cavity for food Carnivores
Specialized Tissues

12. Body Plans
Radial Symmetry
2 Body plans
Polyp
Medusa

13. Body Plans
Polyp
Hydra
Sea Anemone
Coral

14. Body Plans
Medusa
Jellyfish

15. Eating Cnidarians sting their prey with venom
Tentacles then pull the food into the mouth
Where does undigested food go?

16. Reproduction
Both asexually and sexually
How does a polyp reproduce?

17. Coral Coral reefs start with a free-swimming coral larva
Larva attaches to a solid surface

18. Coral Coral polyp reproduces asexually, and so does its offspring
Over time the number of polyps can reach thousands

19. REVIEW 1) Describe the structure of a sponge’s body
2) How do cnidarians capture food?
3) How does a jellyfish capture food?
4) How do polyps reproduce?
5) What are the 2 types of cnidarian body plans?
6) Which body type is free-swimming?
7) What supports the body of a sponge?
8) How do sponges get food?
9) How does coral reproduce?
10) What type of symmetry do sponges have?