A human being loses an average of 40 to 100 strands of hair a day.
133
Enamel is hardest substance in the human body.
61
After age 30, the brain shrinks a quarter of a percent (0.25%) in mass each year.
139
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132
The average person's skin weighs twice as much as their brain.
131
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
Crying literally alleviates stress and uniquely allows humans to decrease feelings of anger and sadness.
24