Medical Facts Did you know...   A trained nose can distinguish up to 10,000 different smells.       A 70-year-old man breathing deeply will inhale half as much air as he did around the age of 20.       By age thirty, the brain starts losing 50,000 cells a day.       Macrophages (large white blood cells) in the body consume more than 300 billion dead or dying red blood cells each day.       The whole exterior of the body is covered by protective layer, which is commonly termed as skin. The skin constantly flakes away, to be replaced by new tissue, once every month. A lifetime of flaking removes 105 pounds of old skins and sees a thousand outer layers. A square inch of the skin is made up of 19 million cells, 625 glands for sweat, and 90 glands for oil. Nineteen feet of intricately woven blood vessels serve the square - inch area, along with 19000 nerve cells. 65 millions of hairs are there each populated by tens millions of bacteria and microscopic mites on them. The outer most layer of skin is termed in medicine as epidermis, which has no life in it.   An adult human is made up of nearly a 100 trillion cells.           Our eyes have 125 million cells to distinguish shades of gray in dim light and 7 million cells that give colour in bright light.           Blood vessels (arteries, capillaries and veins) make up a 60,000-mile system in the human body.       The heart of olfactory system lies deep within the brain. They are two bulbs. The bulbs receive information from 40 million olfactory nerves that hang from the roofs of the nasal cavities. Although these nerves connect directly to the olfactory bulbs, they are shielded from the outside world only by a thin coating of mucus. They are brain's most direct link to physical environment, perhaps a remnant of organs that first developed some 500 million years ago. Surrounding the olfactory bulbs is the limbic region of the brain, which controls emotion and plays a pivotal role in forming and recalling memories. This intimate association explains why odors and emotions are linked. Some researchers suggest that some specific smell makes a person relaxed or even lowered blood pressure. It is a well acquired fact that woman who work in close work places and live in close dormitories, soon acquire synchronized menstrual cycles.       The brain accounts for only 2% of the body weight. It is bathing in 15% of the blood at any given instant and consumes 20% of the nutrition and oxygen.       In just one second, the human body completes about 500 trillion faultless copies of hemoglobin, a protein containing more than 570 amino acids.       Our blood cycles through our body 1,440 times a day.       It takes 25,000 times more soup to taste it than to smell it.       At birth human babies have some 350 bones, more than one and half times the number they will have as adult. Many f the small bones of the infant skeleton eventually fuse to form larger ones, 206 in all.         Food gradually tastes more bland as the number of taste buds on the tongue is reduced about 2/3rds by age 70.         A blood clot is made up of 99% water.       Nothing more vital to human body than water. The water constitutes 61% of the body or about fifty quarts in an average man. About two and half quarts are lost each day through exhalation, perspiration, and excretion. If the loss is not regained by more water intake and if the body looses seven to ten quarts of water more then death is inevitable. Although people have reportedly survived without food, no one has been able to live more than eleven days without water. However, the right protection should be maintained through out the life. If a person increases the intake than normal, then it is possible that he suffers from consequences of excess of water intake. It is rarely seen but such a excess manifests itself in dilution of the mineral concentrations. Because of depletion of the minerals of the body, the cells swell up. Usually the result is uncomfortable bloating. When brain cells become engorged, however, the result could be an excruciating headache, convulsions and or even coma       By the time you grow from infancy to adulthood, you will have about 144 fewer bones.       Even when skin is freshly soaped and rinsed clean, some areas may be home to as many as 20 million bacteria on every square inch.       Only 10 millionths of an inch thick, our lungs can be stretched out to occupy a raquetball court (nearly 750 square feet).       Some 650 muscles sheath the skeleton.       The brain reaches its maximum weight by age 20 – 3 ounces. Over the next 60 years, as billions of nerve cells die within the brain, it loses about 3 ounces.       The body has about 100 trillion cells -- as many as there would be people on 20,000 earths.       There are over 50,000 different proteins in our body.       Many diseases are known to produce characteristic odors on the bodies of the afflicted. Typhoid smells like baking bread, German measles like plucked feathers, yellow fever like a butcher shop, and gangrene like a rotten apple. There are news that at times smell specialist are being asked by the doctors to help them out to diagnose a case which is not being solved but has strange odor. After smelling the affected child, the smell specialist pinpoint the child's condition to which turned out to be a rare metabolic disorder linked to certain food. The appropriate change in diet improved the condition.       The rush of air produced by a cough moves at a speed approaching 600 miles per hour.       The body grows about a third of an inch every night but shrinks to its original size the next day. Gravity makes the difference. In bed, the cartilage disks of the spine are relieved of gravity's downward pull and expand, adding to body length. A prolonged absence of gravity such as that experienced in space can stretch an astronaut by an inch or two.       At any given time, 75 percent of our blood lies in the veins.         Stretched end to end, the digestive tract measure 30 feet.         About a 100 different chemicals transmit information in the brain and along nerves.       The skin sheds nearly a million cells every 40 minutes.       Platelets live for only 10 days.       The heart of a 70-year-old man at rest will pump a quart less blood per minute than it did 40 years earlier.       When we are awake we see many colorful images, the same images are seen in the dreams. Psychologists say that the most exclusive experience is always dreamed of. If that is the case then what about the blind. Blind people interpret their daytime world through hearing, touch, taste, smell, and through balanced emotions. Those who are born blind or lost their vision in early childhood have no concept of seeing with the eyes. Their dreams are rich in sound, movement, and tactual images. Visual pictures are absent in their dreams. A research study revealed that hearing is the most important mode followed by touch.       The lungs are twin sacs of tissues suspended behind the heart. It contains 375 million tiny air cells called as alveoli. These act as small valves at the end of air tubes, or bronchi. The alveoli are involved in active gaseous exchange. It exchanges oxygen with carbon dioxide in the blood. The exchange itself occurs automatically, with the help of simple law of physics. As the pressure is high in alveoli that of oxygen with respect to the pressure of carbon dioxide in the red blood cells, the exchange takes place from the alveoli to the red blood cells. The lungs have interior surface area of 861 square feet. This matches with that of a rug of four by five foot.       One square inch of skin may hold 650 sweat glands, 20 blood vessels and over a 1000 nerve endings.