Lesson 16 of 84 · Crosscutting Concepts
Experiment⭐ 30 XPHomologous Structures: Evidence for Evolution
Crosscutting Concepts.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
Homologous structures are similar body parts in different species that suggest a common ancestor. The arm bones of humans, whales, bats, and dogs share the same basic structure.
Key Words
- fossil record
- species
- heredity
Materials Needed
- colored pencils
- coins (for Punnett squares)
- tape
- index cards
- markers
Safety First
- Use materials only as directed in the experiment.
Steps
Read about Crosscutting Concepts and write down three key facts.
Research one genetic disorder. Create an infographic showing its cause, symptoms, and how it is inherited.
Watch carefully for any changes and note the time.
Create a data table to organize your measurements.
Check Your Understanding
Question 1
1 of 3What are homologous structures?
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
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