Yawns are more contagious among people with closer relationships.
163
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Your heart will pump about 212 million liters in its lifetime.
26
The human brain doesn't stop developing until about 25 years old.
102
Your thumb is about the same size as your nose.
124
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99