Summary
Students will conduct a lab using planaria to observe asexual reproduction.
Materials
- Planaria (may be collected with a piece of liver or chicken suspended in a freshwater pond)
- razor blades
- cups
- egg yolk
- spring water
- student worksheet (attached)
Background for Teachers
Time Needed: To be conducted over several days--About 30 minutes the first day and 5 minutes each days observations are recorded thereafter.
Safety issues or specialized background knowledge:
Be careful using sharp instruments such as razor blades or scalpels.
Instructional Procedures
- Hook activity: Have students obtain their materials--except for the razor blades. Tell them about planaria--they are freshwater worms that can reproduce through fragmentation. Do you think the planaria prefer dark areas or light areas? How could you test that using a sheet of paper? Try it. Name your planaria. Write your name and today's date on your Petri dish using a sharpie.
- Ask students how they think they would like to cut their planaria--horizonal, vertical, diagonal? How many pieces. Have them make their drawings.
- Caution students about using the sharp razor blades or scalpels, instruct them to cut their planaria.
Assessment Plan
Scoring Guide:
1. Students actively participated in the lab and attempted to answer all of the questions …………………4
2. Students answered the questions correctly…………………………...4
Bibliography
Lesson Design by Jordan School District Teachers and Staff.
Created: 12/01/2014
Updated: 02/05/2018
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