Human Body Facts
How the human body is built and how it works.
Your Heart Is About the Size of Your Fist
The human heart is an organ about the size of your fist that pumps blood through your body.
The Human Brain Weighs About Three Pounds
The human brain is a three-pound organ, described by the US National Institutes of Health as the most complex part of the human body.
Skin Is the Biggest Organ of the Human Body
Skin is the biggest organ of the human body, and it is organized into three main layers.
Babies Are Born With About 300 Bones, but Adults Have 206
A baby is born with about 300 bones, many of which fuse together as the child grows to form the 206 bones that adults have.