Every season of Human Body: Pushing the Limits ever, ranked from best to worst by thousands of votes from fans of the show. The best seasons of Human Body: Pushing the Limits!

Sight is the king of the senses. More than 80 percent of what we know of the world comes through our eyes -- without our sight we're lost. In this episode, we reveal the inner workings of our visual system as they've never been seen before, vividly confirming that ancient human adaptations prove no less crucial in modern life.

Sight

The driving force behind every one of us is the most powerful organ in the natural world: the human brain. Our central processing unit generates as many electrical impulses in a single day as all the telephones in the world combined. With new state-of-the-art imagery of this complex, mysterious machine, we reveal how our brain accelerates when faced with intense stress or danger, and taps into its deepest layers to unlock prehistoric survival instincts.

Brain Power

The human body is engineered for strength, power and endurance. Bone is sturdy as concrete but flexible enough to resist breaking and light enough to allow us to be quicker off the mark than a racehorse. Our muscles, ligaments and joints have far greater strength and endurance than we know. In this episode, we feature extraordinary tales of human strength told with stunning see-through "anatomy in motion."

Strength

Less than one-twentieth of an inch below the surface of the skin are the "antennae" that allow us to sense the world around us. This vital layer is the gateway to the original information superhighway -- the nervous system. Millions of nerves carry sensations across the body and up to the brain at hundreds of miles an hour. But our nervous system also has abilities almost beyond imagining.

Sensation

This show covers topics on how the body reacts to moments of extreme stress like being stuck in a cave or running away from forest fires. It is made up of four episodes that all concentrate on a certain aspect of our body when we are "pushed to the limit".

The Best Seasons of Human Body: Pushing the Limits

The Best Seasons of Human Body: Pushing the Limits

Season 1