When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Marie Curie, the Nobel prize winning scientist who discovered radium, died of radiation poisoning.
57
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Out of all the senses, smell is most closely linked to memory.
146
German chemists made a replica of a trophy the size of one molecule.
68
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89