sponges, cnidarians, and worms what is an animal? animal symmetry sponges and cnidarians worms table...
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Sponges, Cnidarians, and Worms
What Is an Animal?
Animal Symmetry
Sponges and Cnidarians
Worms
Table of Contents
Sponges, Cnidarians, and Worms - What Is an Animal?
Structure of Animals
The cells of most animals are organized into higher levels of structure, including tissues,
organs, and systems.
Sponges, Cnidarians, and Worms - What Is an Animal?
Classification of Animals
This branching tree shows how the major animal groupsare related.
Sponges, Cnidarians, and Worms
Asking QuestionsBefore you read, preview the red headings. In a graphic organizer like the one below, ask a what or how question for each heading. As you read, write answers to your questions.
What is a cell? A cell is the basic unit of structure and function in living things.
What is the structure of animals?
The cells of animals are organized into tissues, organs, and systems.
What are the functions of animals?
Animals must obtain food and oxygen, keep a stable environment within their bodies, reproduce, and move about to meet their needs.
How are animals classified? Animals are classified according to how they are related to other organisms.
Question Answer
- What Is an Animal?
Sponges, Cnidarians, and Worms
Links on the Animal Kingdom
Click the SciLinks button for links on the animal kingdom.
- What Is an Animal?
Sponges, Cnidarians, and Worms
End of Section:What Is an Animal?
Sponges, Cnidarians, and Worms
Comparing and ContrastingAs you read, compare and contrast the characteristics of animals with bilateral symmetry and radial symmetry in a Venn diagram like the one below. Write the similarities in the space where the circles overlap and the differences on the left and right sides.
Radial Symmetry Bilateral Symmetry
Many lines of symmetry, no distinct front end, live in water, move slowly
Balanced arrangement of parts, perform all the basic life functions
One line of symmetry, halves that are mirror images, front end with sense organs, quick movement
- Animal Symmetry
Sponges, Cnidarians, and Worms
Links on Animal Symmetry
Click the SciLinks button for links on animal symmetry.
- Animal Symmetry
Sponges, Cnidarians, and Worms
End of Section:Animal
Symmetry
Sponges, Cnidarians, and Worms - Sponges and Cnidarians
Sponges
Structures surrounding the central cavity of a sponge are adapted for different functions.
Sponges, Cnidarians, and Worms - Sponges and Cnidarians
Sponges
The sexual reproduction of sponges involves a larval stage that moves. Adult sponges stay in one place.
Sponges, Cnidarians, and Worms
Calculating a Rate To calculate the rate of water flow in a sponge, divide the volume of water that the sponge filters by the time it takes the water to pass through the sponge.
Flow rate = Volume of water/TimeFor example, a marble-sized sponge filters 15.6 liters of water in a day. How many liters does it filter per hour?
Practice ProblemIn four days, a sponge filters 1,200 L. What is its rate of water flow per day?
300 L/day
- Sponges and Cnidarians
Sponges, Cnidarians, and Worms - Sponges and Cnidarians
Cnidarians
Cnidarians have two basic body plans, the vase-shaped polyp and the bowl-shaped medusa.
Sponges, Cnidarians, and Worms - Sponges and Cnidarians
Cnidarians
Cnidarians use stinging cells to capture food and defend themselves.
Sponges, Cnidarians, and Worms - Sponges and Cnidarians
Cnidarians
The life cycle of a moon jelly has both a polyp and a medusa stage.
Sponges, Cnidarians, and Worms
Feature Sponges Cnidarians
Comparing and ContrastingAs you read, compare and contrast sponges and cnidarians by completing a table like the one below.
Body structure Hollow body with poresPolyp or medusa, central body cavity, tentacles
Cell type that traps food Collar cells Stinging cells
Method(s) of reproduction
Sexual and asexual Sexual and asexual
- Sponges and Cnidarians
Sponges, Cnidarians, and Worms
End of Section:Sponges and Cnidarians
Sponges, Cnidarians, and Worms - Worms
Characteristics of Worms
Biologists classify worms into three major phyla—flatworms, roundworms, and segmented worms.
Sponges, Cnidarians, and Worms - Worms
Life Cycle of a Dog Tapeworm
This flatworm is a parasite that lives in more that one host during its life cycle.
Sponges, Cnidarians, and Worms
Roundworm Numbers
Biologists counted all the roundworms living in a plot of soil. Then they calculated the percentage that lives in different depths of soil.
- Worms
Sponges, Cnidarians, and Worms
Roundworm Numbers
In the first centimeter
Reading Graphs:
Where in the soil was the largest percentage of roundworms found?
- Worms
Sponges, Cnidarians, and Worms
Roundworm Numbers
About 87%
Calculating:
What is the total percentage of roundworms found in the first 3-cm depth of soil?
- Worms
Sponges, Cnidarians, and Worms
Roundworm Numbers
The deeper the soil, the fewer the worms
Drawing Conclusions:
What is the relationship between the depth of soil and the abundance of roundworms in the soil?
- Worms
Sponges, Cnidarians, and Worms - Worms
Segmented Worms
Earthworms and other segmented worms have bodies made up of many linked sections called segments.
Sponges, Cnidarians, and Worms
Using Prior KnowledgeBefore you read, write what you know about worms in a graphic organizer like the one below. As you read, write what you learn.
1. Worms are long and skinny.2. Worms live in the ground and digest soil.3. Worms are slimy and wriggly.
1. Worms have bilateral symmetry.2. Some worms are flat.3. Some worms live in water.4. Some worms are parasites.5. Worms have a nervous system.
What You Know
What You Learned
- Worms
Sponges, Cnidarians, and Worms
More on Worms
Click the PHSchool.com button for an activity about worms.
- Worms
Sponges, Cnidarians, and Worms
End of Section:Worms
Sponges, Cnidarians, and Worms
Graphic Organizer
The Life of a Sponge
Sponge releases sperm.
Sperm enter another sponge and fertilize egg
cell.
Larva develops.Water currents carry away larva.
Larva settles on a surface and
develops into adult sponge.
Sponges, Cnidarians, and Worms
End of Section:Graphic Organizer