20
Lesson 20 of 84 · Human Impacts on Earth
ExperimentBiodiversity and Ecosystems
What You'll Learn
Biodiversity—the variety of life in an ecosystem—makes ecosystems more resilient. Loss of biodiversity from human activities threatens ecosystem stability worldwide.
Key Words
- criteria
- iteration
Materials Needed
- ruler
- markers
- popsicle sticks
- pennies
Safety First
- Dispose of materials properly after the experiment.
- Handle glass items carefully to avoid breakage.
- Do not mix unknown chemicals together.
Steps
Step 1 — Read
Study the diagram and label the parts you recognize.
Step 2 — Do
Build a simple seismograph using a pen, cup, string, and paper. Shake the table and record the marks. Can you detect bigger vs. smaller shakes?
Step 3 — Observe
Compare the before and after states.
Step 4 — Record
Write your conclusion: did the results match your hypothesis? What would you change next time?
Check Your Understanding
Question 1
1 of 3What is refraction?
