1. Sponges and Cnidarians
Chapter 12 Section 2
Introduction to Animals
Student Composed Notes

2. Sponges!!
Sponges interact with many other animals such as worms, shrimp, snails, and sea stars.
Certain sponges contain photosynthetic bacteria and protists that provide oxygen and remove wastes for the sponges.
Chemicals from some sponges today are used for medicine and drugs.
These chemicals also might be used to treat certain forms of arthritis.

3. PICTURES!
Spongebob is best friends with Patrick!

4. Origin of Sponges
Fossil evidence shows that sponges appeared on earth about 600 million years ago.
Many scientists have concluded that sponges probably evolved separately from all other animals.
Sponges living today have many of the same characteristics as their fossilized ancestors.

6. Characteristics of Sponges
Most of 5,000 species of sponges are found in warm, shallow salt water near coastline.
A few species live in freshwater rivers, lakes, and streams.
Some sponges have radial symmetry, but most are asymmetrical
Sponges can be smaller than a marble or larger than a compact car
Organisms that remain attached during their lifetime are called sessile
Sponges are often found in permanent groups called colonies
Sponges were classified as plants until scientists found out that they could not make food the they were classified as animals

7. By Mphokuhle Mathwasa

8. A Spong’s Body Structure
A sponge’s body is a hollow tube that is closed at the bottom and open at the top
Pores are tiny holes throughout the sponges body
Collar cells line the inside of the sponge and use a beating motion to move water through the sponge
Sponges have no tissue, organs, or organ systems!!!
Their bodies have two cell layers made up of several different types of cell

9. A Sponge’s Body Structure (con’t)
Spicules are sharp pointed structures inside a sponge
Spongin are soft bodied skeletons that are commonly found in bath sponges or sponges used for washing cars
Both spicules and spongin provide support for the sponge
James Cunningham

10. Obtaining Food And Oxygen
Sponges filter microscopic food particles such as bacteria, algae, protist, and other materials from water as it is pulled in through their pores.
Oxygen is also removed from the water. The filtered water carries away waste through the top of the sponge.

11. Sponge Reproduction Sponges can reproduce sexually, and asexually.
Most sponge species are hermaphrodites, or animals that produce eggs and sperm in the same body.
After an egg is released and fertilized, it develops into a larva.
Sponge larvae have cilia that help them to swim.
Asexual reproduction occurs through budding and regeneration.
In budding, a bud forms on the sponge and then falls off to grow on its own.

12. Sponge Reproduction
By Kelsey Preston

13. Cnidarians and Cnidarian Environments
Cnidarians are a group of invertebrates that can include colorful corals, tiny hydras, flowerlike sea anemones, delicate jellyfish and the Portuguese man-of-war.
Most cnidarians live in salt water, although many types of hydras live in freshwater.
The sea anemones and most jellyfish (also known as jellies) live as individual organisms.
The hydras and corals form colonies.

14. Cnidarians
Sea Anemones
Jellyfish (Jellies)
Hydra
Coral

15. Two Body Forms Cnidarians have two different body forms.
The polyp- shaped like a vase and usually a sessile
The medusa- bell shaped and free- swimming
A jelly spends most of its life as a medusa floating on a oceans current
Fun Fact: Some species of jellies have tentacles that grow to 30m and trail behind the animal!

17. Body structures of a Cnidarian
Bodies are more complex than sponges bodies
Have 2 cell layer that are arranged into tissues and a digestive cavity where food is broken down
In each cell, oxygen from the water is exchanged for carbon dioxide and other cell waste
They have a system on nerve cells called a nerve net which carries impulses and connects all parts of the organism
Have arm-like structures called tentacles that surround the mouths of most cnidarians
Have a stinging cell which helps it capture food

19. Cnidarians Obtaining Food
By Christopher Mendoza

20. Cnidarians Obtaining Food
Cnidarians are predators, meaning they hunt animals for food.
Some cnidarians sting their prey with toxins, killing or stunning it.
The tentacles of cnidarians bring the food to the mouth, where they swallow it.
The threadlike structures used for stinging are either sticky or barbed.
Cnidarians only have one opening, so undigested food comes out of the mouth, too.
Cnidarians Obtaining Food

21. The Portuguese Man of War can kill a human in one sting.
Pictures
The Portuguese Man of War can kill a human in one sting.
The Turritopsis nutricula is a jellyfish that could choose to be immortal!
Even though jellyfish are predators, they are also prey

22. Reproduction Cnidarians reproduce asexually and sexually.
Polyp forms reproduce asexually by producing buds that eventually fall of the Cnidarians.
Polyp also reproduce sexually by producing sperm and egg.
Medusa forms of cnidarians have two stages of reproduction a sexual stage and asexual stage.
eggs are fertilized by sperm form another medusa of the same species and develop into larvae.
The larvae eventually settle down and grow into polyps.
When young medusa bud off the polyp, the cycle begins again.

23. Pictures

24. Origin of Cnidarians Originiated 600 million years ago
Medusa body was first form of cnidarian
Most cnidarian fossils are corals

26. Corals and It’s Importance
-It takes millions of years to form large reefs like in the Caribbean.
-Coral reefs are productive ecosystems and extremely important in the ecology of tropic water.
-Coral reefs are homes to many organisms that provides pearls and shells.
-Like sponges, coral produces a chemical to protect itself from diseases and other organisms.
-These chemicals that they produce might provide humans with medicine for cancer.
-Some coral is used to replace missing sections of bones for humans.
By: Parker Moore

27. Coral Pictures By: Parker Moore