Sponges and Cnidarians

Chapter 12 Section 2Introduction to Animals

Student Composed Notes

Sponges!!

1. Sponges interact with many other animals such as worms, shrimp, snails, and sea stars.

2. Certain sponges contain photosynthetic bacteria and protists that provide oxygen and remove wastes for the sponges.

3. Chemicals from some sponges today are used for medicine and drugs.

4. These chemicals also might be used to treat certain forms of arthritis.

PICTURES!

• Spongebob is best friends with Patrick!

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.

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

By Mphokuhle Mathwasa

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

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

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.

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.

Sponge Reproduction

By Kelsey Preston

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.

Sea Anemones

Jellyfish (Jellies)

Hydra

Cnidarians

Coral

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!

http://images.google.com/url?sa=i&rct=j&q=cnidarians+eating&source=images&cd=&cad=rja&docid=Vuw4PYOYcFScHM&tbnid=j-bq30muU3Z-4M:&ved=0CAUQjRw&url=http://www.mesa.edu.au/friends/seashores/cnidaria.html&ei=uTEJUZWeCOaW2QXd_4DADg&psig=AFQjCNG_-P7Hi2UczOvrgcIh8zhGmRoLRQ&ust=1359643438792887

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

Cnidarians Obtaining Food

By Christopher Mendoza

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.

Pictures

The Turritopsis nutricula is a jellyfish that could choose to be immortal!

The Portuguese Man of War can kill a human in one sting.

Even though jellyfish are predators, they are also prey

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.

Pictures

Origin of Cnidarians

• Originiated 600 million years ago • Medusa body was first form of cnidarian• Most cnidarian fossils are corals

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=m7qZcr9MKaaVIM&tbnid=cL9blKLuKz6j-M:&ved=0CAUQjRw&url=http%3A%2F%2Fdictionary.reference.com%2Fbrowse%2Fjellyfish&ei=UysJUbaRGYeQ2QXvp4D4CQ&bvm=bv.41642243,d.dmQ&psig=AFQjCNFPIc7_klYrSKLybfjO484c2VD5Og&ust=1359641789847917

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

Coral Pictures By: Parker Moore