The average sperm cell swims at 8 inches per hour.
76
Enamel is hardest substance in the human body.
61
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Your thumb is about the same size as your nose.
124
The average person's skin weighs twice as much as their brain.
131
It takes about 20 seconds for a red blood cell to circle the whole body.
102
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46