Introduction:  Scientists have identified and named more than 1.8 million species of animals.  It is estimated that there are another 3 million to 30 million more to identify.  Animals are classified into two major groups; vertebrates and invertebrates.  Invertebrates are classified as animals without a backbone and make up about 97% of all animal species.  Simple invertebrates include sponges, cnidarians, flatworms, and roundworms.

Task:  Follow the hyperlinks below to answer the following questions.

Sponges:

1. What Kingdom and Phylum do sponges belong to?

2. List four different Classes of sponges.

3. How many known species of sponges are there?

4. List five different body shapes that sponges can have.

5. What do sponges eat?

6. How do sponges eat?

7. What is the name of the specialized cell where food is collected?

8. Define Benthic.

Sketch this
9.  Sketch and label the sponge’s external anatomy.
10.  Define osculum.

Define
11. Define Porifera.
12. What are the two species of sponges pictured (common name)?

Cnidarians:

13.   Where does the word Cnidarian come from and what does it mean?
14.    Name the four major groups of Cnidarians and list an example of each.
15.   Click on the links of each of the four groups of Cnidarians and sketch one example animal from each group.

Questions 16-21
16.  Why are Cnidarians considered simple but deadly?
17.   List the two different body types of Cnidarians and sketch an example of each.
18.   What is the coiled thread-like stinger that all Cnidarians have called?
19.   Describe how the stinger protects the animal.
20.  Are Cnidarians deadly to humans? Why or why not?
21.   Name three species of Cnidarians pictured (common name).

Coral Reef
22.   What is a coral reef?
23.   List seven examples of organisms that are sheltered by coral reefs.
24.   What are the two types of coral?  List an example of each.
25.   Where are coral reefs found in the world?
26.   Describe a Fringing Reef.
27.   Describe a Barrier Reef.
28.   Describe a Carol Atoll.
29.   How are coral reefs in danger?

Flatworms:

30.   About how many species are know in this group?
31.   How does a flatworm move?
32.   What part of a flatworm helps it sense light?
33.   How many openings does a flatworm have (for eating and getting rid of wastes)?
34.   How long can a flatworm be?

Four classes of Flatworms
35.   Go to the bottom of the link above and click on each of the four classes of flatworms.  Read the description of each type of flatworm, then list the common name and write a brief summary from each description.

Roundworms:

36.   How many known species of roundworms are there?
37.   How many eggs can some species of roundworms lay in a single day?
38.   How many unknown species of roundworms are there said to be?

Types of Roundworms
39.   Name three common types of roundworms.
40.   Where do roundworms live?
41.   Describe the body shape of a roundworm.

Ascaris
42.   Where does Ascaris live?
43.   What part of the human body do adult Ascaris worms live?
44.   How many eggs can be produce a day?
45.   How long can adult Ascaris worm live?
46.   At the bottom of the web page are four pictures of Ascaris roundworms.  Describe what you see in each picture.