Hubel and Wiesel won the 1981 Nobel Prize in Physiology or Medicine. Here's a video explaining their experiment.

Did you know that when you fall down, the earth falls up to meet you? Explore the counterintuitive equation that describes gravity.

The truth is that we'd be blobs of water and bone without our muscles. They are the things that hold us up and allow our skeleton to support our body weight. But how do they form and develop? In the same way our bones grow and develop.

Are typical balance disorders the same as those that an astronaut experiences when he/she reenters the earth's gravity? "A balance disorder is a condition that makes you feel unsteady or dizzy, as if you are moving, spinning, or floating, even though you are standing still or lying down. Balance disorders can be caused by certain health conditions, medications, or a problem in the inner ear or the brain."

The inner ear has two functions: the first is hearing and the second is balance. It is a warren of tubes filled with fluid encased within the temporal bone of the skull. The bony tubes also contain a set of cell membrane-lined tubes. The bony tubes are called the bony labyrinth filled with perilymph fluid, which the membranous labyrinth tubes are filled with endolymph. This is where the cells responsible for hearing are located (the hairy cells of Corti).

Living in space is not the same as living on Earth. Many things are different. Our bodies change in space. The way we stay clean and neat is different too. Learn how astronauts stay strong, clean, and neat.

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