How the Human Body Works
Understand the living machinery beneath your skin. Discover how your organs collaborate, how muscles generate movement, and how your body regulates itself every second.
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.
24 levels across 3 sections, about 48 minutes end to end, roughly 10 days at five minutes a day. It moves through Signals and Movement; The Internal Supply Lines; and Control, Communication, and Defense. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in How the Human Body Works
- Homeostasis is an active, continuous internal balancing act, not a passive state
- The body constantly monitors and adjusts its internal chemistry regardless of external extremes
- Heart rate speeds up to deliver oxygen and fuel whenever cells demand it, including during stress, fear, or immune defense
- Muscular movement is only one of many triggers that raise cellular metabolic demand
- Breathing triggers fire based on the buildup of carbon dioxide waste in the blood
- Sensors monitor rising acidity from carbon dioxide much more sensitively than falling oxygen levels
- Sweat requires surface evaporation to pull heat away from the body
- Shivering uses tiny, rapid muscle twitches to produce metabolic heat
- Blood vessels widen near the skin surface to radiate surplus heat outward
- Negative feedback begins when an internal sensor spots a deviation from a set point
- The body activates a countermeasure that directly pushes the metric back toward the target
- Reaching the normal set point removes the trigger and naturally turns off the response
- Skeletal muscle fibers only generate force by shortening (pulling)
- Muscles cannot actively push or lengthen themselves
- An opposing muscle (like the triceps) on the other side of the joint must contract to pull the limb back
- Tendons connect muscle to bone so contracting muscles can move the skeleton
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 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.
Here's what playing it feels like
A real question from this course. Take your best guess.
What happens inside your body when you walk from freezing snow into a cozy, hot room?
Get it right to open this lesson and 23 more in the app.
Where How the Human Body Works takes you
- 1
Signals and Movement
- Reading Your Body's Vital Signals
- Bones, Joints, and Leveraged Muscle
- 2
The Internal Supply Lines
- Oxygen Delivery and Circulation
- Digestion and Fuel Extraction
- Filtration and Fluid Balance
- 3
Control, Communication, and Defense
- Rapid Electrical Signaling
- Hormones and Daily Cycles
- Immunity, Skin, and Tissue Repair
3 sections · 8 units · 24 levels. Built to play, not to enroll.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
How the Human Body Works is taught in the Explain Like I'm 5 style: no big words. promise.. 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.