·   The Heart

            The heart of an adult beats about 70 to 80 beats per minute, 100,000 times every day, 40 million times a year and in 70 years it will have beaten 2½ billion times.  A female heart beats about 10 times per minute faster than a male’s.  The rate can increase to as much as 200 per minute during heavy exercise. As a pump it produces enough pressure to shoot a stream 30 feet, produce enough energy in an hour to lift 2000 lb. 3 feet off the ground, and efficiently circulate 50 million gallons over the average lifetime. In one year, the average human heart circulates from 770,000 to 1.6 million gallons of blood through the body. This is enough fluid to fill 200 tank cars, each with a capacity of 8,000 gallons. There are enough tiny blood vessels called capillaries that if placed end to end they would stretch over 2 times around the earth.  All this is done with just over a gallon of blood which circulates 1 000 times in a single day through the body on a daily 60,000-mile journey, 168,000,000 miles in a lifetime. 25 trillion cells travel through the bloodstream but a stack of 500 would only measure 0.04 inches high. The human heart rests between beats. In an average lifetime of 70 years, the total resting time is estimated to be about 40 years.

            Red blood cells live for a period of only four months and travels between the lungs and other tissues 75,000 times before returning to the bone marrow to die, being replaced by the bone marrow at the rate of 2 to 3 million a second.  Men have more blood, 1.5 gallons as compared to 0.875 gallons for women. The most common blood type in the world is Type O accounting for about 46% of the world's population. However, in some areas, other blood groups predominate. The most rare, Type A-H, has been found in less than a dozen people since the type was discovered.  According to research, the risk of heart attack is higher on Monday than any other day of the week. A child has 60 000 miles of blood vessels, in an adult there are 100 000. The stethoscope was invented so that doctors could listen to a woman's heart without having to touch her. The native people of the Andes Mountains in South America have 2 to 3 more quarts of blood in their bodies than people who live at lower elevations.

·   The Eyes

            As you focus on each word in this sentence, your eyes swing back and forth 100 times a second, and every second the retina performs 10 billion computer-like calculations.  The eyes can perceive more than 1 million simultaneous visual impressions, are able to discriminate among nearly 8 million gradations of color, can distinguish about 500 different shades of gray, and take in more information than the world’s largest telescope.  Each time the eye blinks over 200 muscles move and you blink 25 times a minute or over 6 million times each year.  The retina inside the eye covers about 650 square millimeters and contains some 137 million light-sensitive cells; 130 million rod cells for black and white vision and 7 million cone cells for color vision. To focus all this the muscles of the eye move 100,000 times a day. An eye weighs 1.25 ounces. By the age of 60, our eyes have been exposed to more light energy than would be released by a nuclear blast. Sight accounts for 90 to 95 percent of all sensory perceptions.

            The human eye sees everything upside down, but the brain turns it right side up, with an average field of vision encompassing a 200-degree wide angle. Your ears and nose continue to grow throughout your entire life but your eyes are the same size from birth to death. A bird's eye takes up about 50 percent of its head; human eyes take up about 5 percent the head. To be comparable to a bird's eyes, human eyes would have to be the size of baseballs.  If you go blind on one eye, you'll loose only one-fifth of your vision but lose all your depth perception.  The only part of the human body that has no blood supply is the cornea; it takes its oxygen directly from the air.

            Newborn babies are not blind but have approximately 20/50 vision and can easily discriminate between degrees of brightness. The daughters of a mother who is colorblind and a father who has normal vision will have normal vision, however the sons will be colorblind.  While 7 men in 100 have some form of colorblindness, only 1 woman in 1,000 suffers from it. The most common form of color blindness is a red-green deficiency.  People are the only animals in the world who cry tears. Onion Tears are caused by an irritant in onions known as brominates molecules, which react with the water on the eye to produces an acid which the eye removes by producing tears. Those stars and colors you see when you close and rub your eyes are called phosphenes

            Two out of three adults in the United Sates wear glasses at some time.  While reading a page of print, the eyes do not move continually across the page. They move in a series of jumps, called "fixations," from one clump of words to the next.  Though more comfortable with daylight, given enough time to adjust, the human eye can, for a time, see almost as well as an owl's. The sensitivity of the human eye is so keen that on a clear, moonless night, a person standing on a mountain can see a match being struck as far as 50 miles away. Much to their amazement, astronauts in orbit were able to see the wakes of ships.  When you have a black eye, you have a bilateral periorbital hematoma.  While reading a page of print, the eyes do not move continually across the page. They move in a series of jumps, called "fixations," from one clump of words to the next.  The pupil of the eye expands as much as 45 percent when a person looks at something pleasing.

·   The Ears

Our hearing is so sensitive it can distinguish between hundreds of thousands of different sounds. Between ages 30 and 70, the ears may be a quarter-inch longer due to the fact that cartilage is one of the few tissues that continue to grow as we age.  A human can hear the tick of a watch from 6 meters in very quiet conditions. Sounds too low for human beings to hear are called infrasonic.  The easiest sound for the human ear to hear, and those which carry best when pronounced, are, in order, "ah," "aw," "eh," and "oo."  Permanent hearing loss can result from prolonged exposure to sounds at 85 decibels (0 decibels is the threshold for hearing). For comparison, a busy street corner is about 80 decibels, a subway train from 20 feet is 100 decibels, a jet plane from 500 feet is 110 decibels and loud thunder is 120 decibels. A rock band amplified at close range is 140 decibels, more than 100,000 times as loud as the level that will produce permanent hearing loss.  The African bushman lives in a quiet, remote environment and has no measurable hearing loss at age 60.

·   The Nose

The nose cleans, warms, or cools, filters, and humidifies over 500 cubic feet of air every day.  It monitors and classifies over 10,000 different odors and the sense of smell is so keen that it can detect the odors of certain substances even when they are diluted to 1 part to 30 billion. A human can detect one drop of perfume diffused throughout a three-room apartment. It is totally impossible to sneeze with your eyes open a sneeze can exceed the speed of 100 mph, and when you sneeze, all bodily functions stop, even the heart. Most people by the age of sixty have lost 40 percent of their ability to smell. Your thumb is the same length as your nose.

·   The Mouth

            The average human has about 10,000 taste buds. Those on the tongue are divided into four groups; the tip taste buds sense sweetness; those at the back sense bitterness; the sides sense saltiness and sourness. All the more complex tastes are made up of combinations of the basic four. However, not all taste buds on the tongue. Some are under the tongue; some are on the inside of the cheeks; some are on the roof of the mouth. Some can even be found on the lips, which are especially sensitive to salt. The sense of taste can detect sweetness in a solution of 1 part sugar to 200 parts water and one gram of salt in 500 liters of water. The average lifespan of a human being's taste bud is 7-10 days. By age sixty, most people have lost half of their taste buds. The strongest muscle in the body is the tongue and every person has a unique tongue print.  Pigs, dogs, and some other animals can taste water, but people cannot. Humans don't actually taste water; they taste the chemicals and impurities in the water. 85% of the population can curl their tongue into a tube.

            The tooth is the only part of the human body that can't repair itself and tooth enamel is the hardest of all substances manufactured by the human body.  Each tooth contains about 55 miles of canals for a total of over 1700.  There are 20 baby teeth and 32 adult teeth.  False teeth are often radioactive. Approximately 1 million Americans wear some form of denture; half of these dentures are made of a porcelain compound laced with minute amounts of uranium to stimulate fluorescence. Without the uranium additive, the dentures would be a dull green color when seen under artificial light.  If you are right-handed, you will tend to chew your food on the right side of the mouth. If you are left-handed, you will tend to chew your food on the left. A pack-a-day smoker will loose approximately 2 teeth every 10 years.

            It requires the use of 72 muscles to speak a single word.  Whispering is more wearing on your voice than a normal speaking tone.  Whispering and shouting stretch the vocal cords.  A normal person has two true vocal chords and two false vocal chords, which have no direct role in producing sound. The mouth makes one liter of saliva a day and over a lifetime, produce enough to fill two swimming pools.  Every time you lick a stamp, you're consuming 1/10 of a calorie.  Up to the age of six or seven months, a child can breathe and swallow at the same time. An adult cannot do this. Seeing another person yawn makes it likely that you will yawn yourself. Thinking about, even reading about yawning, can cause a yawn.

·   The Skin

            The largest and heaviest organ is the skin, with a surface area of about 25 square feet and weighs about 6 pounds.  The epidermis, the outermost layer of the skin, sheds itself at a rate of about a million cells every 40 minutes. Humans shed about 600.000 particles of skin every hour, about 1.5 pounds a year, and grow all new outer skin cells about every 27 days, almost 1.000 new skins a lifetime. By 70 years of age, an average person will have lost 105 pounds of skin. Floor dust contains 90% dead skin.

            The skin is only about as deep as the tip of a ballpoint pen but the sense of touch is more refined than any device ever created.  A human can detect the wing of a bee falling on your cheek from a height of one centimeter.  There are 45 miles of nerves in the skin of a human being.  When we touch something, we send a message to our brain at 125 mph.  In one square inch of skin we have nine feet of blood vessels, 600 pain sensors, four yards of nerve fibers, 1300 nerve cells,9000 nerve endings, 36 heat sensors, 75 pressure sensors, 650 sweat glands, 60,000 pigment cells, 100 sweat glands, 3 million cells, and an average of 32 million bacteria.  Your fingernails grow four times as fast as your toenails.

            Perspiration is odorless; it is the bacteria on the skin that creates an odor.  The skin of the armpits can harbor up to 516,000 bacteria per square inch, while drier areas, such as the forearm, have only about 13,000 bacteria per square inch. There are about 2 million sweat glands in the average human body. The average adult loses 540 calories with every liter of sweat and men sweat about 40% more than women. There are approximately 250,000 sweat glands in your feet and they sweat as much as 8 ounces of moisture per day. You perspire a total of 1.5 pints a day.

            The tips of fingers and the soles of feet are covered by a thick, tough layer of skin called the stratum corneum. Identical twins do not have identical fingerprints. No two sets of prints are alike, including those of identical twins. The fingerprints of koala bears are virtually indistinguishable from those of humans, so much so that they could be confused at a crime scene.  Humans are the only primates that don't have pigment in the palms of their hands. A simple, moderately severe sunburn damages the blood vessels to such an extent that it takes four to fifteen months for them to return to their normal condition. First-degree burns affect only the very top layers of the skin; second-degree burns are midway through the skin's thickness.  Third-degree burns penetrate and damage the entire thickness of the skin.  Varicose veins are stretched, dilated veins whose valves do not work properly.

·   The Bones

            The average human body has 208 bones, 54 are in the hands; 52 are in the feet, 28 above the neck, 6 are in the ears and 22 are in the skull.  The skeleton of an average 160-pound body weighs about 29 pounds. A newborn baby has 330 but as the child grows, some of the bones join together to give fewer bones in total. Babies are born without kneecaps. They don't appear until the child reaches 2-6 years of age. The longest human bone is the femur or thighbone, which is 48 cm. long. It is so strong that it can support 30 times the weight of a man!  The strongest bone in the body, the thighbone, is hollow. Ounce for ounce, it has a greater pressure tolerance and bearing strength than a rod of equivalent size in cast steel. 

            The mineral content, porosity, and general makeup of human bone is nearly identical to some species of South Pacific coral. The two are so alike that plastic surgeons are using the coral to replace lost human bone in facial reconstructions.  The body has over 100 joints.  The average person's hand flexes its finger joints 25 million times during a lifetime.  Most people's legs are slightly different lengths. Giraffes and humans have the same number of vertebrae in their necks. The pop you get when you crack your knuckles is actually a bubble of gas bursting generated by imploding synobial fluid.  The "funny bone" is not a bone it is a nerve. The structural plans of a whale's, a dog's, a bird's and a man's 'arm' are exactly the same.

·   The Muscles

            The human body has over 600 muscles accounting for 40% of the body's weight and 1/3 of those muscles are used just to blink the eyes. The strongest muscle in the body is the tongue.  Jaw muscles can provide about 200 pounds of force for chewing. To focus the eye muscles move 100,000 times a day.  To give the leg muscle the same amount of exercise would require a 50-mile walk. It takes 17 muscles to smile, 43 to frown and every 2000 frowns creates one wrinkle. The longest name for a muscle is: Levator Labii Superioris Alaeque Nasi. It is a two-inch muscle that elevates the tip of the mouth. The simple act of walking requires the use of 200 muscles in the human body. The smallest human muscle is in the ear, which is a little over 1 mm long. If all the muscles in an average body in to one muscle it could produce about 2,000 tons force. The longest muscle in the human body is the sartorius. This narrow muscle of the thigh passes obliquely across the front of the thigh and helps rotate the leg to the position assumed in sitting cross-legged. No one truly has double joints. Contortionists are actually able to stretch the fibrous tissues known as ligaments. Ligaments hold organs in place and fasten bones together. Ligaments normally restrict the movements of certain joints, but some folks find that their ligaments are more flexible than others.  Between the time of death and the onset of rigor mortis in a human body, the contraction of the muscles can cause the body to turn over on its side.

·   Energy

            The body gives off the amount of heat equivalent to a 100-watt light bulb and overall produces 25,000 BTUs.  26 calories are burned in a one-minute kiss and banging ones head against a wall will use 150 calories an hour. In a lifetime the average US resident eats more than 50 tons of food and drinks more than 13,000 gallons of liquid. This includes 8 spiders. 75% of your body heat escapes through your head.  The body uses 48 kg of ATP a day (ATP is the energy the body produces during cellular respiration).  A person will die from total lack of sleep sooner than from starvation.  Death will occur about 10 days without sleep, while starvation takes a few weeks. Small animals like bats and shrews consume up to one and one half times their body weight in food every day. For an adult male, this would be like eating 1,000 quarter-pound cheeseburgers a day, or about 50 Thanksgiving dinners a day. Moderate dancing burns 250 to 300 calories an hour. Twenty minutes of moderate dancing will elevate heart rate up to aerobic levels. One study found polkas, swing dancing, and waltzes to be particularly effective for weight loss.  If you yelled for 8 years, 7 months and 6 days, you would have produced enough sound energy to heat one cup of coffee.  Every human body is naturally radioactive. Our tissues contain traces of the radioactive isotopes Potassium-40 and Carbon-14, which are absorbed by all living organisms from the environment.  Every person has nearly 400,000 radioactive atoms disintegrating into other atoms in his or her body each second.  Each body cell contains an average of 90 trillion atoms, 225 million times that 400,000 disintegrating.  Women burn fat more slowly than men, by a rate of about 50 calories a day.  Laughing is aerobic. It provides a workout for the diaphragm and increases the body's ability to use oxygen. Laughing lowers levels of stress hormones and strengthens the immune system. Six-year-olds laugh an average of 300 times a day. Adults only laugh 15 to 100 times a day.  Most deaths in a hospital are between the times of 4pm and 6pm, the time when the human body is at its weakest.  There are 110 calories consumed during an hour of typing only 30 more than those used while sleeping.

·   Organs and Glands

Even if the stomach, the spleen, 75 percent of the liver, 80 percent of the intestines, one kidney, one lung, and virtually every organ from the pelvic and groin area are removed, the human body can still survive. The average Human bladder can hold 13 ounces of liquid.  There are 35 million digestive glands in the stomach.  The pituitary gland - responsible for producing the hormone that regulates growth - is only the size of a pea and weighs little more than a small paper clip.  The liver is often called the body's chemical factory and performs over 500 functions.  If 80 percent of your liver were to be removed, the remaining part would continue to function. Within a few months, the liver would have reconstituted itself to its original size. The liver is a gland, not an organ.  The liver stretches across almost the width of the body, occupying a space about the size of a football. It weighs more than 3 lbs. The kidney consists of over 1 million little tubes, and the total length of the tubes in both kidneys runs to about forty miles.

·   Ingredients

The body contains hydrogen, copper, zinc, cobalt, calcium, manganese, phosphates, nickel, sulfur, potassium, carbon iron and silicon. The average human body contains enough: sulfur to kill all fleas on an average dog, carbon to make 900 pencils, potassium to fire a toy cannon, fat to make 7 bars of soap, phosphorus to make 2,200 match heads, water to fill a ten-gallon tank and enough iron to make a 3 inch nail.  The hydrochloric acid of the human digestive process is so strong a corrosive that it easily can eat its way through the iron of an automobile body. Yet, it doesn't endanger the stomach's sticky mucus walls.  Smart people have more zinc in their hair.  The body’s daily requirement of vitamins and minerals is less than a thimbleful.

·   Cells

The human body consists of about 60 trillion cells, and each cell has about 10,000 times as many molecules as the Milky Way has stars.  Except for your brain cells, 50,000 of the cells in your body will have died and been replaced with others, all while you have been reading this sentence. Three hundred million cells die in the human body every minute. The largest cell in the human body is the female reproductive cell, the ovum. The smallest is the male sperm.  The average adult has between 40 and 50 billion fat cells.

·   DNA

All of the DNA in an adult human body could fit inside one ice cube, but if unwound, stretched out, and joined end to end, it would reach from the earth to the sun and back again more that 400 times.  Scientists estimate that they could fill a 1,000-volume encyclopedia with the coded instructions in the DNA of a single human cell if the instructions could be translated to English.

·   Content

If you were freeze dried, like coffee, 90% of your weight would be the real you, and 10% would be the little critters that call your body their home?  If all of the spaces between the nucleus's of the atoms making up an average human body were removed the person would be the size of half a flea. However they would still weigh the same.

·   Other

Asparagus Urine: The first suspect was proposed in 1891.  It was proposed that as your body metabolizes asparagus, it produces a smelly chemical, a metabolite called methanethiol, which your discriminating kidneys see fit to dump into the bladder. Other culprits suspected are S-Methyl Thioesters, or six sulfur-containing compounds.  Research says just 22 percent of survey respondents experience asparagus urine but the problem proved to be one not of producing the stinky urine but of being able to sniff it out. 

The average human body is worth about 25 dollars.

People are the only animals in the world who cry tears.

Undertakers report that human bodies do not deteriorate as quickly as they used to. The reason, they believe, is that the modern diet contains so many preservatives that these chemicals tend to prevent the body from decomposition too rapidly after death.

In the average lifetime, a person will walk the equivalent of 5 times around the equator.

The average adult stands 0.4 inch (1 cm) taller in the morning than in the evening, because the cartilage in the spine compresses during the day.

The thumb is such a major player in the human body that it has a special section, separate from the area that controls the fingers, reserved for it in the brain.