Body & Brain
21 interactive videos. Watch each one, then try the idea live. Free, no account.
Your Amazing Heart
Two pumps in one. 4 chambers, 4 valves, 100,000 beats a day. Never naps.
How You Breathe
Your lungs don't suck — the diaphragm does. Air pressure does the rest.
How Food Becomes You
A 9-meter disassembly line that turns lunch into bones, blood, and brain cells.
How Your Ears Hear
Air vibration → eardrum → 3 tiny bones → fluid → hair cells → brain. A Rube Goldberg machine.
Meet Your Neuron
86 billion tiny trees in your head, talking to each other. That's you.
Germs vs Viruses
Bacteria are alive. Viruses aren't really. Your immune system fights both differently.
Your Skeleton
206 bones. Not dead. Living tissue rebuilding itself, making blood, and fixing breaks.
Muscles Only Pull
Every push you make is a pull from the opposite muscle. We have antagonistic pairs.
Your Blood's Army
Liquid armor + oxygen taxi + emergency repair crew. The 4 components of blood.
Your Skin Shield
Your largest organ. 3 layers. Sensors, sweat glands, blood vessels. Replaces itself monthly.
How Your Tongue Tastes
Five tastes, not four — and the tongue map is a myth. Most of 'taste' is actually smell.
How Your Nose Smells
Lock-and-key chemistry: ~400 receptors + 1 trillion patterns. Direct line to memory.
How You Grow
Cells double. Bones stretch from growth plates. Hormones drive it. Sleep makes it happen.
How Your Skin Feels
Touch isn't one sense — it's five. Different sensors for pressure, vibration, stretch, temp, pain.
How Memory Works
Neurons that fire together wire together. Each recall actually rewrites the memory.
How You Learn Things
Practice physically rewires your brain. Myelin makes signals 100× faster. Sleep locks it in.
Why You Need Sleep
Brain takes out the trash. Memories move to long-term storage. Body heals. Skip it = pay later.
Why Vegetables Help
Vitamins + minerals + fiber + plant chemicals. The raw materials your body literally cannot make.
Dreams & Imagination
REM sleep + judge offline + random firing = the nighttime sandbox where anything goes.
Emotions in the Brain
Feelings aren't mystical. Specific regions + chemicals = your full emotional palette.
Your Body Clock
A tiny brain region keeps 24-hour time using light. Screens at night confuse it.