Explore the internal mechanics of the human body through pioneering graphics and case studies.

Our bodies respond quickly to survive in cold temperatures.

Fear is a learned behavior.

In order to regenerate a functional heart, Dr. Ott takes skin cells and reprograms them into stem cells.

What Recker does during this crucial growing period will change the structure of his brain forever.

Freya's bones in her racket arm have become thicker to cope with her intense workouts.

We learn to work together by reading the emotions and facial expressions of others.

The story of how our body deals with damage and repair can be told through Kate's feet.

As Lew pushes himself, his body demands more oxygen to keep it going.

What determines when we start puberty has until recently been a mystery.

Danny demonstrates how new motor skills must be learned and developed with practice.

From an early age, we learn how to control the movements of our bodies.