1. Sponges
Chapter 9 Section3

2. Live all over the world (oceans, freshwater rivers and lakes)
Sponges

3. Sponge: Body Structure
Invertebrate animals
No body symmetry
Never have tissues or organs
Looks like a hollow bag
Large opening at one end and tiny pores covering the surface
Spikes support and protect sponges body
Sponge: Body Structure

4. Sponge: Obtaining Food and Oxygen
Eats tiny single-celled organisms
Collar cells that line central cavity, trap the tiny organisms
Jelly-like cells inside sponge digest, or break down, the food
Sponges get oxygen from water
Sponge: Obtaining Food and Oxygen

6. Sponges: Reproduction
Asexually
Budding: small new structures grow from the sides on an adult sponge
Buds eventually break free and begin new life
Sexually
Sponges produce both sperm cells and egg cells (do not have separate sexes)
Sperm cells released in water, enter another sponge, fertilize its eggs, larva develops
Larva: immature form of an animal that looks very different from the adult
Sponges: Reproduction

8. Cnidarians
Chapter 9 Section3

9. Cnidarians Jellyfish, corals, and sea anemones
Invertebrates that have stinging cells to capture food and protect themselves
Take food into central body cavity
Cnidarians

10. Cnidarians: Body Structure
Two different body plans (vase and bowl)
Radial symmetry
Central hollow cavity
Tentacles containing stinging cells
Cnidarians: Body Structure

11. Vase-shaped body plan is a POLYP
Sea anemone
Mouth opens at top
Tentacles spread out from around mouth
Most are attached to underwater surface
Body Structure: Polyp

12. Body Structure: Medusa
Bowl-shaped body plan is a MEDUSA
Jellyfish
Adapted for a swimming life
Mouths open downward and tentacles trail down
Body Structure: Medusa

13. Obtaining Food Use stinging cells to catch animals they eat (prey)
Contains threadlike structure with spines
Uses tentacles to pull prey to mouth
Takes food into central body cavity
Expels undigested food through mouth
Obtaining Food

14. Unlike adult sponges, many cnidarians move to escape danger and to obtain food
Jellyfish?
Sea Anemones?
Movement

15. Reproduction Asexual Reproduction Sexual Reproduction
Hydras, corals, and sea anemones
Sexual Reproduction
Jellyfish
Reproduction

16. Colony Life in a Colony a group of many individual animals
Stony corals and Portuguese man-of- war
Life in a Colony

17. Stony Coral a coral reef is built by cnidarians
coral reefs are home to more species of fishes and invertebrates than any other environment on Earth
Coral polyps produce hard, stony skeletons around their soft bodies
Stony Coral

18. Portuguese Man-of-War
Contains as many as 1,000 individuals that function together as one unit
Top: gas filled chamber, allows colony to float
Bottom: polyps with different functions drift below
Some catch prey and help with digestion and reproduction
Portuguese Man-of-War