How Your Body Works
Like Duolingo, but for How Your Body Works. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
Free during early access · No credit card · iPhone & Android

Key ideas in How Your Body Works
- Bones are constantly broken down and replaced by new cells
- Ball-and-socket shapes allow movement in all directions
- Bone tissue requires a blood supply to stay healthy
- Hinge joints limit movement to a single plane
- Physical stress or exercise signals bones to become denser
- Fixed joints provide stability without motion
- Bones are living, changing tissues rather than static objects
- Joint shapes dictate the specific movement of limbs
- The ribs shield the heart and lungs from impact
- Bone marrow is the primary site of blood cell production
- The gaps between ribs allow the chest to expand for breathing
- Bones are hollow to house this 'factory' without being too heavy
- The skull is a solid dome because the brain does not need to expand like the lungs
- Blood cells must be constantly replenished by the skeleton
- The skeleton's role in protecting vital organs
- The role of bone marrow in blood production
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives How Your Body Works the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
Imagine you are a conductor waving a baton in wide, sweeping circles. What specific joint shape allows your shoulder to move in all directions?
Get it right to open this lesson and 11 more in the app.
Where How Your Body Works takes you
Discover the incredible machinery inside you. Learn how your bones, muscles, and organs work together to keep you moving, breathing, and thinking.
- 1
The Framework of Movement
- The Living Scaffold
- The Engines of Action
- 2
The Internal Support Systems
- The Fuel and Exhaust Loop
- The Command Network
2 sections · 4 units · 12 levels. Built to play, not to enroll.
You pick the voice
How Your Body Works is taught in the The Storyteller style: every lesson is a story. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start How Your Body Works today.
Download Tomo, search How Your Body Works, and play your first lesson in under a minute.