The average sperm cell swims at 8 inches per hour.
76
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Yawns are more contagious among people with closer relationships.
163
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
The average person's skin weighs twice as much as their brain.
131
Your thumb is about the same size as your nose.
124
Every year your body replaces 98% of your atoms.
119