Human Mysteries - part 2

Continuing on the mysteries of the human body......

11. Your body has enough iron in it to make a nail 3 inches long.

12. Earwax production is necessary for good ear health. It protects the delicate inner ear from bacteria, fungus, dirt and even insects. It also cleans and lubricates the ear canal.

13. Everyone has a unique smell, except for identical twins, who smell the same. 

14. Your teeth start growing 6 months before you are born. This is why one out of every 2,000 newborn infants has a tooth when they are born.

15. A baby's head is one-quarter of its total length, but by the age of 25 will only be one-eighth of its total length. This is because people's heads grow at a much slower rate than the rest of their bodies.

16. Babies are born with 300 bones, but by adulthood the number is reduced to 206. Some of the bones, like skull bones, get fused into each other, bringing down the total number.

17. It's not possible to tickle yourself. This is because when you attempt to tickle yourself you are totally aware of the exact time and manner in which the tickling will occur, unlike when someone else tickles you.

18. Less than one third of the human race has 20-20 vision. This means that two out of three people cannot see perfectly.

19. Your nose can remember 50,000 different scents. But if you are a woman, you are a better smeller than men, and will remain a better smeller throughout your life.

20. The human body is estimated to have 60,000 miles of blood vessels. 

21. The three things pregnant women dream most of during their first trimester are frogs, worms and potted plants. Scientists have no idea why this is so, but attribute it to the growing imbalance of hormones in the body during pregnancy. 

22. The life span of a human hair is 3 to 7 years on average. Every day the average person loses 60-100 strands of hair. But don't worry, you must lose over 50% of your scalp hairs before it is apparent to anyone.

23. The human brain cell can hold 5 times as much information as an encyclopedia. Your brain uses 20% of the oxygen that enters your bloodstream, and is itself made up of 80% water. Though it interprets pain signals from the rest of the body, the brain itself cannot feel pain.

24. The tooth is the only part of the human body that can't repair itself.

25. Your eyes are always the same size from birth but your nose and ears never stop growing.