Lesson 38 of 84 · Spacetime
Lesson⭐ 30 XP🚀 StarbaseBacteria and Viruses
Spacetime.
🎯 Your mission
Learn the rule. Then catch nature using it.
⚡ The twist
Gravity is invisible — but it shapes everything.
Mind = Blown
🌟 The light from the closest star (after the sun) takes 4 years to reach you.
Make a hypothesis first
Before you check: which is closer?
What You'll Learn
Bacteria are tiny single-celled organisms that live almost everywhere, and while some cause disease, many are helpful, like those that break down food in our intestines. Viruses are even smaller and can only reproduce by invading the living cells of another organism.
Key Words
Tap a word to see its definition.
Steps
Read the introduction and identify the main idea of this lesson.
Compare the skeletal structures of a bird wing, human arm, and whale flipper using diagrams. Identify homologous bones and write what this tells us about common ancestry.
Use your senses (except taste) to describe what you notice.
Write a summary of your findings in 3-5 sentences.
Check Your Understanding
Question 1
1 of 3Which animals go through metamorphosis?
Where you see this in real life
Every sunrise and every shadow is this idea in action.
Stretch Challenge
Try this in real life this week.
Look at the moon tonight. Notice its shape. Look again in 3 days.
For the dinner table
“If you could visit any planet, which would you pick and why?”
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.
Checkout complete lesson on Spacetime for 9th Grade
Get the full Spacetime track as a printable PDF — all lessons, worksheets, and answer keys.