The human body

Human Mysteries:



The Human Body is a treasure trove of mysteries, one that still
confounds doctors and scientists about the details of its working.
It's not an overstatement to say that every part of your body is a
miracle. Here are fifty facts about your body, some of which will
leave you stunned...or...



1. It's possible for your body to survive without a surprisingly large
fraction of its internal organs. Even if you lose your stomach, your
spleen, 75% of your liver, 80% of your intestines, one kidney, one
lung, and virtually every organ from your pelvic and groin area, you
wouldn't be very healthy, but you would live.



2. During your lifetime, you will produce enough saliva to fill two
swimming pools. Actually, Saliva is more important than you realize.
If your saliva cannot dissolve something, you cannot taste it.



3. The largest cell in the human body is the female egg and the
smallest is the male sperm. The egg is actually the only cell in the
body that is visible by the naked eye.



4. The strongest muscle in the human body is the tongue and the
hardest bone is the jawbone.



5. Human feet have 52 bones, accounting for one quarter of all the
human body's bones.



6. Feet have 500,000 sweat glands and can produce more than a pint of
sweat a day.



7. The acid in your stomach is strong enough to dissolve razor blades.
The reason it doesn't eat away at your stomach is that the cells of
your stomach wall renew themselves so frequently that you get a new
stomach lining every three to four days.



8. The human lungs contain approximately 2,400 kilometers (1,500 mi)
of airways and 300 to 500 million hollow cavities, having a total
surface area of about





70 square meters, roughly the same area as one side of a tennis court.
Furthermore, if all of the capillaries that surround the lung cavities
were unwound and laid end to end, they would extend for about 992
kilometers. Also, your left lung is smaller than your right lung to
make room for your heart.



9. Sneezes regularly exceed 100 mph, while coughs clock in at about 60 mph.



10. Your body gives off enough heat in 30 minutes to bring half a
gallon of water to a boil.



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.



26. By 60 years of age, 60% of men and 40% of women will snore.



27. We are about 1 cm taller in the morning than in the evening,
because during normal activities during the day, the cartilage in our
knees and other areas slowly compress.



28. The brain operates on the same amount of power as 10-watt light
bulb, even while you are sleeping.  In fact, the brain is much more
active at night than during the day.



29. Nerve impulses to and from the brain travel as fast as 170 miles
per hour. Neurons continue to grow throughout human life. Information
travels at different speeds within different types of neurons.



30. It is a fact that people who dream more often and more vividly, on
an average have a higher Intelligence Quotient.



31. The fastest growing nail is on the middle finger.



32. Facial hair grows faster than any other hair on the body. This is
true for men as well as women.



33. There are as many hairs per square inch on your body as a chimpanzee.



34. A human fetus acquires fingerprints at the age of three months.



35. By the age of 60, most people will have lost about half their taste buds.



36. About 32 million bacteria call every inch of your skin home. But
don't worry, a majority of these are harmless or even helpful
bacteria.



37. The colder the room you sleep in, the higher the chances are that
you'll have a bad dream.



38. Human lips have a reddish color because of the great concentration
of tiny capillaries just below the skin.



39. Three hundred million cells die in the human body every minute.



40. Like fingerprints, every individual has an unique tongue print
that can be used for identification.



41. A human head remains conscious for about 15 to





20 seconds after it has been decapitated.



42. It takes 17 muscles to smile and 43 to frown.



43. Humans can make do longer without food than sleep.  Provided there
is water, the average human could survive a month to two months
without food depending on their body fat and other factors. Sleep
deprived people, however, start experiencing radical personality and
psychological changes after only a few sleepless days. The longest
recorded time anyone has ever gone without sleep is 11 days, at the
end of which the experimenter was awake, but stumbled over words,
hallucinated and frequently forgot what he was doing.



44. The most common blood type in the world is Type O. The rarest
blood type, A-H or Bombay blood, due to the location of its discovery,
has been found in less than a hundred people since it was discovered.



45. Every human spent about half an hour after being conceived, as a
single cell.  Shortly afterward, the cells begin rapidly dividing and
begin forming the components of a tiny embryo.



46. Right-handed people live, on average, nine years longer than
left-handed people do.



47. Your ears secrete more earwax when you are afraid than when you aren't.



48. Koalas and primates are the only animals with unique fingerprints.



49. Humans are the only animals to produce emotional tears.



50. The human heart creates enough pressure to squirt blood 30 feet in the air.