20

Lesson 20 of 84 · Scientific Argument

Lesson

Biodiversity 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

  • amplitude
  • reflection

Steps

Step 1Read

Study the diagram and label the parts you recognize.

Step 2Do

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 3Observe

Compare the before and after states.

Step 4Record

Write your conclusion: did the results match your hypothesis? What would you change next time?

Check Your Understanding

Question 1

1 of 3

What is refraction?