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

criteria
iteration
wavelength

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 3

What is refraction?