1. Sponges and Cnidarians
6th Grade
Chapter 17 Section 2
Notes pg

2. Do Now… Write down all of the letters in the Alphabet (use uppercase).
Circle the letters that have radial symmetry in red.
Circle the letters that have bilateral symmetry in blue.
Circle the letters that are asymmetrical in yellow.
*Some letters may have more than 1 type of symmetry!*

3. Objectives Students will…
Describe the structures that make up sponges and cnidarians.
Compare how sponges and cnidarians get food and reproduce.
Review Self Check Homework

4. Sponges (pg. 501-502) Characteristics of Sponges A. Filter Feeders
- Sponges filter food from the water that flows through their bodies.
-Do not make own food!
B. Body Support and Defenses
- spicules and spongin protect sponges from predators
What are spicules and spongin?

5. Sponges C. Sponge Reproduction
- sponges can reproduces sexually and asexually
There are not male/female sponges!
See chart on pg. 502 for more details.
D. Sponges are Sessile
-Adult sponges do not move from place to place.

6. Cnidarians Characteristics of Cnidarians
Include Jellyfish, Sea Anemones, Hydra and Coral
Have radial symmetry
Are hollow bodied animals with 2 cell layers that are organized into tissues.
Have tentacles around their mouth to help catch food

7. Cnidarians-Body Forms
2 different body forms
Polyp-vase shaped body (sea anemone or hydra)
Medusa-free swimming bell shaped (jelly fish)
Some cnidarians go through both stages during their life cycle

8. Cnidarian Reproduction (Pg. 503)
Main Stages of Reproduction
1. Larva attaches to a surface
2. Polyp grows
3. Young medusa buds off (asexual reproduction)
4. Sexual reproduction-male medusa releases sperm and female releases eggs
5. New larve are produced

9. Sponges and Cnidarians

10. To Review Name one difference between sponges and cnidarians.
For Next Time….
Read pgs
Define polyp and medusa on index cards

11. Flatworms and Roundworms
6th Grade
Notes pg

12. Do Now… How do sponges and cnidarians get their food?
Sponges-filter food out of the water as it comes to them
Cnidarians-actively capture prey with their tentacles that have stinging cells.

13. Objectives Students will
Differentiate between flatworms and roundworms through the creation of a foldable

14. Flatworm/Roundworm Foldable
Create foldable according to teacher instructions
Characteristics
Flatworms
Roundworms
Body Shape
Body Openings
Body Construction
Digestive System
Picture

15. Review Foldable Characteristics Flatworms Roundworms Body Shape
Long and Flat
Long and round
Body Openings
One
Two
Body Construction
Three Layers
Fluid-filled cavity between 2 tubes
Digestive System
Most do not have their own digestive system
Have a digestive system
Picture

16. Tapeworms Type of parasitic flatworm
To survive, it lives in the intestines of its host (including humans!)
Since it does not have a digestive system, it absorbs nutrients from digested material in the host’s intestine.
How do tapeworms get into humans?
Tapeworm length activity

17. Videos
Why parasites might not be all that bad
Flatworms
Roundworms

18. For Next Time… Read pgs. 506-508
Define organ, mollusks, mantle, gills and radula on index cards.
Due on Friday, 11/1.