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How the Human Body Works, a free science course on Tomo

How the Human Body Works

Discover the incredible machinery running beneath your skin every second. Learn how your organs coordinate, why your body produces familiar everyday sensations, and what it takes to keep you moving, thinking, and alive.

Like Duolingo, but for How the Human Body Works. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.

21 levels across 3 sections, about 42 minutes end to end, roughly 8 days at five minutes a day. It moves through Deciphering Your Daily Signals; Motion, Sensation, and Control; and Defense, Renewal, and Maintenance. It starts from scratch.

21 bite-size levelsAbout 5 minutes each

Free forever · No credit card · iPhone & Android

Barnaby the Badger, the guide who teaches the How the Human Body Works course
How the Human Body Works
with Barnaby the Badger
21
Levels
3
Sections
5
Min/day
What you'll learn

Key ideas in How the Human Body Works

  • Sweat cools the body when moisture evaporates off warm skin
  • The liver and kidneys filter toxins, not sweat glands
  • Sweat is mostly water and salt designed for heat regulation
  • Exercising muscles generate carbon dioxide that builds up in the blood
  • The brain's breathing centers monitor rising carbon dioxide levels, not falling oxygen
  • The gasp response is an urgency to blow off excess carbon dioxide
  • The brain's thirst center triggers only after blood volume drops and blood becomes more concentrated
  • Waiting for thirst means mild dehydration is already underway
  • The body conserves water before it alerts you to drink
  • Shivering uses fast, involuntary muscle contractions to create friction and heat
  • Goosebumps pull hair shafts erect to trap a protective layer of air against the skin
  • A deep yawn draws in cooler room air and increases blood flow to cool the brain
  • Yawning stretches facial muscles and provides a mild alertness reset
  • Yawning does not measurably increase blood oxygen levels compared to normal breaths
  • Saliva contains chemical enzymes that immediately start breaking complex starches into simple sugars
  • Digestion begins chemically in the mouth, not just mechanically through chewing
Why not just Google it

You've tried the other tabs

Wikipedia

Thirty open tabs. Four facts you actually kept.

YouTube

You watched. You nodded. By Sunday it was gone.

ChatGPT

One answer, then back to scrolling.

Online courses

Eight weeks. You meant to finish. You didn't.

Tomo gives How the Human 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.

Try a question

Here's what playing it feels like

A real question from this course. Take your best guess.

Why We Sweat and Gasp

Which organs actually handle filtering and clearing toxins from your blood?

Get it right to open this lesson and 20 more in the app.

Course map

Where How the Human Body Works takes you

  1. 1

    Deciphering Your Daily Signals

    • Making Sense of Instant Body Feedback
    • The Energy Converter: From Bite to Fuel
  2. 2

    Motion, Sensation, and Control

    • The Mechanical Frame: Bones, Joints, and Muscles
    • Wiring and Instant Reactions: The Nervous Highway
  3. 3

    Defense, Renewal, and Maintenance

    • The Body's Border Control: Immunity and Repair
    • The Internal Plumbing: Circulation and Filtration
    • The Nightly Overhaul: Sleep and Rhythms

3 sections · 7 units · 21 levels. Built to play, not to enroll.

New

Tomo is in ChatGPT

Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.

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How it's taught

You pick the voice

This course
The Bestie

How the Human Body Works is taught in the Bestie style: your friend who just gets it. 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 the Human Body Works today.

Download Tomo, search How the Human Body Works, and play your first lesson in under a minute.