Interesting facts and misconceptions about the human body.

1. Facts About the Human
Body

2. Blood
• It takes about 20 seconds for blood
to travel through your body.
• Blood is never blue, it just varies
from a dark red, to a light red. The
blue-green coloring we see is due to
the color of our veins and how light
passes through.

3. The Brain
• The brain itself can't feel pain.
• We don't use 10% of our brain, we
use most of it, and the parts we
don't really use, are basically useless.
Having more of something doesn't
always make it better.

4. Eyes
• Our eyes stay the same size our
whole life, while our ears and nose
keep growing until death.
• Women blink twice as much as
men.
• Humans are the only animals that
produce tears emotionally.
• You can't cry in space, tears won't
fall without gravity

5. The Body
• Eating before swimming doesn't actually
cause cramps.
• Hair doesn't grow back thicker, it's just blunt
after being shaved.
• Split ends can't be fixed, hair is dead, so you
have to cut it. Shampoo and conditioner only
make hair smooth.

6. Misconceptions
• Cracking your knuckles doesn't cause arthritis.
The cracking you hear is either nitrogen
moving, or your tendons snapping over your
bones (which happens over time anyway)
• The redhead gene isn't going extinct, it's
recessive, so many people have it, they just
don't know it.

7. After Death
• After death, your body dries out and your skin
recedes, causing it to look like your hair and
nails have grown

8. Extras
• It only takes about 7 pounds of pressure to rip
your ear off.
• Alcohol doesn't kill brain cells, it just weakens
connective tissue and makes it feel that way.
The brain can repair itself, so damaged tissue
repairs relatively fast