Invertebrates of the Animal Kingdom: Sponges & Cnidarians

7th Grade Life Science

Sponges in Kingdom Animalia

•Sponges belong to the Phylum - Porifera

•Phylum Porifera – Sponges •Asymmetrical.

I. Sponges A. Sponges were once believed to be plants

because they look plantlike and adult sponges do not move.

B. But sponges take food into their bodies, which classifies them as animals.

C. Sponges have been on the earth for 540 million years.

Yellow sponge eating the coral.

Barrel sponge filters food particles into its osculum. Fish are not food for the sponge.

About Sponges: Video

D. The Structure of Sponges a. The phylum of the sponge is Porifera which means “having pores”

b. The body of a sponge is like a bag that is pierced all over with openings called pores.

E. Look at the Sponge

1.) Together let’s Sketch a sponge in the box below.

2.) Label a pore, the osculum, collar cells, and spikes.

3.) Draw arrows showing the direction the water flows through the sponge’s body.

Sponge Sketch

E. Getting Food and Oxygen from Water a. Sponges feed by straining food particles from water.

b. Collar cells on the inside of the central cavity trap these food particles and digest them.

• Video! Sea Sponge filter feeding. • http://www.youtube.com/watch?v=T7E1rq7zHLc

Copyright © 2010 Ryan P. Murphy

Learn more about Porifera / sponges at… http://www.enchantedlearning.com/subjects/invertebrates/sponge/

c. Sponges get oxygen from the water through diffusion.

d. In diffusion, molecules of a substance move from an area of high concentration to areas of low concentration. Oxygen is more concentrated in the water than in the sponge cells so the oxygen travels from the water into the sponge cells.

e. Diffusion also carries waste out of the sponge cells into the water.

F. Spikes

a. Sponges bodies are supported by a network of spikes.

b. Those spikes can be as sharp as needles.

G. Sponge reproduction a. Sponges reproduce sexually and asexually.

b. Budding is one form of asexual reproduction. 1.) The new sponge grows on the sides of an adult

sponge and eventually break off and live on their own.

a. In sexual reproduction water carries sperm from one sponge into the pores of another sponge.

b. The sperm fertilizes the sponge’s egg cells.

c. The fertilized egg grows into a larvae. d. A larva is the immature form of an animal that looks very different from the adult form.

Why Sponges are Worth Studying:

• https://www.youtube.com/watch?v=taTB9kzA-IE

Assignment: Coloring a Sponge

• Read the article about Sponges

• Answer the questions. You must find the answer in text. • Highlight or underline the answer and write the

question # that it answers

• You may begin coloring your Sponge = be sure to follow the instructions and color the sponge correctly