The Physics of Living Systems
Discover how the fundamental laws of mechanics, fluids, and thermodynamics dictate how living organisms survive, move, and sense the world. Bridge the gap between biology and physics through real biological machinery.
Like Duolingo, but for The Physics of Living Systems. 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 Physical Forces and Biological Form; Thermodynamics and Molecular Machines; and Electrodynamics, Light, and Sensory Physics. It assumes you already know the basics.
Free forever · No credit card · iPhone & Android

Key ideas in The Physics of Living Systems
- Body mass and compressive load scale with volume as length cubed
- Bone weight-bearing strength scales only with cross-sectional area as length squared
- Isometric scaling would make bones experience twice the mechanical stress
- Rubner's 2/3-power rule assumed heat dissipation through surface area limits metabolism
- Kleiber's 3/4-power law reflects space-filling fractal distribution networks
- Hierarchical branching networks minimize hydrodynamic resistance and transport energy
- Tendons stretch on landing to store kinetic and gravitational potential energy as strain energy
- Elastic recoil returns over 90% of stored mechanical work during push-off
- Tendons allow attached muscle fibers to stay nearly isometric while generating peak force
- Rigid hydroxyapatite crystals provide high compressive stiffness
- Flexible collagen fibers absorb energy through plastic deformation and uncoiling
- Self-weight acts as an axial compressive load that triggers sudden lateral deflection
- Critical buckling height scales with the trunk radius to the 2/3 power (Greenhill's limit)
- Tapering and high stem elastic modulus increase stability against elastic buckling
- Alternating microstructures force propagating cracks to blunt and twist, raising toughness
- Viscous drag overwhelms inertia at microscopic scales, making the Reynolds number tiny.
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 The Physics of Living Systems 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.
Picture a creature's leg bone as a supportive pillar. As the animal grows larger, what determines how much load that bone can support?
Get it right to open this lesson and 20 more in the app.
How to learn The Physics of Living Systems, step by step
Go in order. 21 short levels across 3 sections, about 42 minutes in all, five minutes a day.
- 1
Physical Forces and Biological Form
- Scaling Laws and Biomechanical Structure
- Life in Moving Fluids
- 2
Thermodynamics and Molecular Machines
- Diffusion and Molecular Motion
- Bioenergetics and Chemiosmosis
- Protein Folding and Physical Force Networks
- 3
Electrodynamics, Light, and Sensory Physics
- Bioelectricity and Signal Conduction
- Photons, Optics, and Quantum Biology
3 sections · 7 units · 21 levels. Built to play, not to enroll.
Questions about The Physics of Living Systems
How do I learn The Physics of Living Systems?
Go in order: start with Physical Forces and Biological Form, then Thermodynamics and Molecular Machines, then Electrodynamics, Light, and Sensory Physics. On Tomo that's 21 short levels, about 42 minutes in all, played five minutes a day. Start free and play the first level in under a minute.
Is there a Duolingo-style app for The Physics of Living Systems?
Yes. Tomo works like Duolingo: short daily lessons, streaks and quick quizzes. The Physics of Living Systems is one of its free courses, and you can type any other topic to get a course of your own.
Is The Physics of Living Systems free?
Yes. The Physics of Living Systems is playable on Tomo's free plan, which doesn't expire. No credit card, no waitlist. Download the app and start your first lesson.
How long does it take to learn The Physics of Living Systems?
21 levels across 3 sections, about 42 minutes of play in total. It's built for five minutes a day, so you finish it a little at a time instead of all at once.
Do I need any background to start The Physics of Living Systems?
No. It's pitched at an intermediate level, so it starts where you are and builds up. If you can tap a phone, you can start.
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
The Physics of Living Systems is taught in 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 The Physics of Living Systems today.
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