1. Phylum Porifera
Sponges
Porifera “paw-rif-er-uh”
Cnidarians

2. Porifera Sponges Living on Earth for at least 540 million years
Most sponges live in the ocean
Arctic to the tropics
shallow water to depths of several hundred meters
They are dry sponges were use for
Bathing
Cleaning

3. Porifera What is a Sponge?
Sponges are placed in the phylum Porifera (poh-RIF-ur-uh) which means “pore-bearers.”
Sponges have tiny openings, or pores, all over their bodies
Sponges are sessile, meaning that they live their entire adult life
They have irregular symmetry

4. Porifera Why are sponges considered animals?
Sponges are multicellular, heterotrophic, have no cell walls and contain only a few specialized cells.
Water flow
Collar cells or choanocytes (koh-an-uh-sytz) are cells that use flagella to move a steady current of water through the sponge. Water leaves thru the osculum

5. Porifera: Structure Specialized cells of sponges:
Collar cells or choanocytes – Use flagella to move a study current of water through the sponge.
Osculum – A large hole at the top of the sponge
Spicule – spike-shaped structure made of chalklike calcium carbonate or glasslike silica
Amoebocyte – move around within the walls of the sponge and carry food to other cells
Softer sponges have an internal skeleton made of spongin, a network of flexible protein fibers. These are the sponges used as natural bath sponges.

6. Porifera: Digestion
Sponges are filter feeders – take microscopic food particles from the water.
As water moves through the sponge, food is trapped and engulfed by collar cells (choanocytes) that line the body cavity
Then, food gets passed to amebocytes who take the food to the rest of the cells in the body

7. Porifera How do they breathe?
Sponges rely on the movement of water through their bodies to carry out body functions:
Respiration – oxygen obtained from the water
Excretion – removal of wastes into the water

8. Porifera How do they reproduce?
Reproduction can be sexually or asexually.
Adults produce gemmules which can withstand harsh conditions and grow into an adult sponge
Reproduce asexually by regeneration – tear of a piece of sponge and a complete new sponge will appear.
Sponges are hermaphrodites – each adult can act as either the female or the male in reproductin.

9. Porifera How important are sponges to the environment?
Many sponges are large and have irregular shapes and provide habitats
Commensalism and partnerships
EX: bacteria provide food and oxygen to the sponge while the sponge provides protected area.

10. Porifera Types of Sponges Calcareous sponges
Found in shallow waters around the world
Spikes made of calcium carbonate (lime)

11. Porifera Types of Sponges Glass sponges
Skeleton consists of crystalline silicon dioxide
Generally found in deep, tropical waters

12. Porifera Types of Sponges Demospongiae (Bath sponges)
Skeleton is elastic (spongin) fibers
Found in the Caribbean
Encrusting Sponge

13. Phylum Ctenophora
Comb Jelly

14. Ctenophora
Ctenophores (Greek for “comb-bearers”) have eight “comb rows” of fused cilia arranged along the sides of the animal (red rows)
The cilia beat and propel the animal through the water

15. Ctenophora
Ctenophora are commonly known as comb jellies and are voracious predators
50 species
Most species are planktonic carnivores and transparent which feed on zooplankton
Light-scattering cilia and bioluminescence
Lack stinging cells but capture prey by sticky cells called colloblasts
Favorite food of sea turtles
Lack stinging cells

16. Ctenophora Reproduction Most are hermaphroditic
Release egg and sperm in water, where sperm must find the egg to fertilize it
Fertilized eggs develop through larval stage that hatches into an adult; no medusa stage
Sea gooseberry

17. Hydras, jellyfishes, sea anemones and corals
Phylum Cnidarians
Hydras, jellyfishes, sea anemones and corals

18. Cnidarians What is a cnidarian (ny-DAYR-ee-n)? 10,000 species
Soft-bodied, carnivorous animals
Stinging tentacles arranged in circles around their mouths
Simplest animals to have radial symmetry and specialized tissues.

19. Cnidarians Specialized cells of cnidarians
Cnidocytes – stinging cells that are located along their tentacles
Nematocyst – poison-filled, stinging structure that contains a tightly coiled dart.
In this picture, a sea anemone captures a fish that has brushed the trigger of the nematocyst. When triggered, the filament inside uncoils and shoots a barb into the animal

20. Cnidarians Form and Function in Cnidarians
Simple organisms and only a few cells thick
Responses to the environment are carried out by specialized cells and tissues.
Life cycle that includes two different-looking stages:
Polyp stage
Medusa stage

21. Cnidarians Polyp stage Cylindrical body with armlike tentacles.
Mouth points upward
Polyps are usually sessile

22. Cnidarians
Medusa Stage
Motile
Bell-shaped body
Mouth on the botton

23. Cnidarians How do Cnidarians feed?
After paralyzing its prey, cnidarian pulls the prey through its mouth into its gastrovascular cacity