The human tongue is capable of distinguishing just four basic tastes. Its surface is covered by thousands of nerve endings called taste buds, which are divided into four different groups.

Thos on the tip of the tongue sense sweetness and those at the back sense bitterness.  The ones at the sides sense saltiness and sourness. There are other taste buds scattered around the inside of the mouth. The main tasters of sour and bitter are actually in the roof of the mouth.

So things like honey and sugar are tasted with the tip of the tongue. However beer, which can have a bitter taste, is best enjoyed with the back of the tongue. Specialist beer tasters will tell you to drink it by pouring it to the back of your tongue, avoiding the tip.  Salty crisps and chips are tasted by the side of the mouth and things like sour lemons, vinegar and things like that also get tasted by the taste buds at the sides.

More complex tastes are made up of combinations of the basic four flavours.  Young adults have around 8000 taste buds, but the nerve endings start to die after the age of 45, so that older people usually have only around 6500 taste buds.

Much of what we perceive as flavour in food is in fact a mixture of taste and smell, which is why food seems to lose its taste when the nose is blocked during a cold.

Damage to taste buds can be very painful and make it very difficult to taste food properly. Even those very tiny ulcers that sometimes affect the tongue can badly affect the ability to taste.

Such was the case early this September when I noticed a marked increase in these bug-like specks floating in front my left eye; and since I had vision only in that eye,  I immediately phoned my local ophthalmologist to find out what was wrong.  Indeed, after two consecutive visits on a Monday and a Tuesday, he insisted that I make an appointment for the next day at the Baylor Eye Clinic at the Baylor College of Medicine, which is part of the Baylor College of Medicine in the Texas Medical Center in Houston, Texas.

After a rushed 250 mile trip to Houston, however, the diagnosis was less alarming than I thought it would be, although the specialist I visited counseled that in the future I would just have to put up with the inconvenience.  Specifically, he likened having a Posterior Vitreous Detachment to sitting in a chair–the longer I sat in a particular chair, the less I would notice it.  I also soon learned that my brother had had a PVD in his right eye the year before and found the experience very distracting.  He had even contemplated a vitrectomy, a procedure that drains the eyeball of liquefied vitreous gel and replaces it with saline solution.  However, such an elective operation is not recommended in most cases since if anything goes wrong, it may also cause a permanent retina detachment.

Although most adults if they live long enough eventually have a PVD in one or both eyes, it probably occurs sooner in the nearsighted, since myopic vision elongates the shape of the eyeball, thus increasing the likelihood of PVD, or if one has had cataract surgery, YAG laser eye surgery, or has diabetes.  Because I’m nearsighted, have had cataract and secondary cataract surgery, and two laser eye surgeries, it’s not too surprising that my vitreous gel had liquefied and subsequently detached.  However, in all the years I have gone to a retina specialist (Since 1966, I have travelled to Houston for biannual or annual appointments), no one has mentioned this possibility.

All the same, I have had at least two checkups since I returned to my hometown from Houston and will have one more with a local retina specialist in two weeks.  A slight chance exists that a PVD could cause a retina tear or detachment, so it’s wise to monitor my vision.  In the following weeks, I’ve had a narrower field of vision than I’ve had previously, and I was a little more clumsy at first, even tripping over the dishwasher door,  but I’m gradually “fitting into my chair”. 

Still, I wish my retina specialist or my ophthalmologist had told me this was part of the aging process.  Even so, at age 57, I look forward to many years of vision, provided I continue to have regular checkups and alert a retina specialist should I see lightning flashes or if a sudden dark curtain falls upon my field of vision.

A group of test subjects had magnetic imaging brain scans performed at the beginning and again at the end of the experiment, and were trained to juggle three balls. They had to practice for 30-minutes daily and over a 6-week period before having their second brain scan. There was a 5% increase in white matter in a region of the brain called the intraparietal sulcus, the area that is responsible for reaching/grasping manipulative tasks that also involves peripheral vision.

These findings have researchers excited as this suggests that other similar treatments could lead to cures or improvements for persons afflicted with degenerative diseases involving ‘white matter’ degeneration. In Multiple Sclerosis, the white matter is degraded and does not allow electrical signals to transmit effectively to the spinal cord making sufferers endure physical inabilities.

While this 5% increase of white matter in the region associated with peripheral dexterity and task performance is encouraging, not all the jugglers tested developed their juggling skills with equal proficiency. This is revealing in itself. It seems to be as much their attempt to learn this complicated and unfamiliar physical task and not just the prowess of execution that is the key. The adage of ‘use it or lose it’ comes to mind except this seems to build new material, not just maintain existing material. Exercising a muscle can increase the muscle size, but ‘learning a new skill’ has never before been shown to increase brain mass. Sufferers of degenerative diseases of the brain might someday soon benefit from these findings as well as congenital defects although it has not been yet shown that generating new material necessarily replaces degenerated material. It seems suggestive that it might or could.

Juggling is Good for the Brain?

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Basically, learning to juggle will most probably not prevent nor stave-off the onset of Multiple Sclerosis of other degenerative diseases like Alzheimer’s Disease, but it does demonstrate that the cause of MS (decreased or faulty electrical transmission between the brain and spinal cord) might be manipulated by other means (via chemical, other artificial stimulation such as increased electrical impulses, etc.) to improve the quality of life for those afflicted, reduce the symptoms or hopefully even prevent the disease in the first place.

•  pheromone – the pheromone that lends an aura, macho men dominated. It attracts and arouses women on a primordial level, and women report that they are better and stronger orgasms during sexual intercourse.
• friendly pheromone- is known as a friendly pheromone. They seek to make available to nice, friendly, and others.
•  middle ground- knows that there is a middle ground between the two. People say it is very similar to pheromone, not much has all this macho.
• Use Clutch found – in pheromones for women. Couplings are, of course, women who during their time of ovulation. The fittings are used to attract people.

Pheromones are fragrances and perfumes at a time. Some people use perfume pheromones that simple or scented body spray. So they need not use any other perfume. Unscented products can be mixed with cologne, perfume or body sprays. Both pheromones are used in the same places where we, as a rule for another body spray or perfume.
Pheromones “work” for products, both male and female, and pheromones are used to gain sexual attraction of the opposite sex.

Guys do not leave it look for you – Fat or slim, tall or short, beautiful or not sexy macho – if you can use pheromones to women sexually attractive. After the women smell of pheromones in the pheromone product, which she feels attracted to you. Try using pheromone products and you will see that women are beginning to show you more attention, more eye contact, more appointments, and of course more sex.
The same goes for women. If you love someone, and I do not pay much attention to how you want to try – “Attack” pheromone. If it all around you – make sure pheromones sprayed on your body and you start to feel the difference. Many women use this “weapon” to the guy they want.
Pheromones to increase your power of seduction, you bring more success in business and improve many social situations, people comfortable around you and your mood.

Every human being has bacteria living inside them.  This bacteria assists with the breakdown of foods to allow the nutrients to be absorbed by your body.  There’s of course, an unintended side effect to these little helpers and their careful assistance: additional gases.

Much of the smell accompanied by your farts is due to the sulfur rich compounds being broken down by these bacteria.  For this reason, a person who’s diet is heavy in sulfurous foods, such as meat or eggs, will tend to have a stronger odor when farting.

The good news is, you’re not the only one.  The average person farts about 12-14 times per day.  Even the lady-folk who tend to deny it.  The only real difference is that some people are prouder than others about the event.  Even the best “holders” are incapable of preventing 100% of all farts, they just sneak out when they’re sleeping, instead.

An important consideration when trying to hide the smell of your farts: when running away from the smell, your movement can literally drag it along with you.  And for those in cold climates, you can SEE farts.  You can see them the same way you can see your breath.  Warm moisture is a terrible, terrible give-away.

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Every living creation in this world needs air to breath for living. Air supplies us with oxygen which is essential for our bodies to live. However, living in a fast growing age of technology, millions of people now live in areas where urban smog, very small particles, and toxic pollutants pose serious health concerns. Smog is a kind of air pollution and it is referred to as a mixture of harmful substance that can often be seen as a fog in the air.

Modern smog does not usually come from coal but from vehicular and industrial emissions that are acted on in the atmosphere by sunlight to form secondary pollutants that also combine with the primary emissions to form photochemical smog. Smog- producing air pollutants can cause serious health effects and can even cause premature death. According to scientific researches, smog doesn’t just ruin your view; it poses serious health risks, especially to children and senior citizens.

It must be well understood that the problem on air pollution is not only limited within the urban centers; it can also be found outside of major urban centers. Air pollutants can be carried hundreds of miles by winds and can thus affect areas far-removed from the source of pollution.

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Smog is known to cause or aggravate respiratory illnesses such as asthma, chronic bronchitis, and emphysema especially to young children (age of 10 below) or older person (70 and older), and people with heart and lung conditions who are particularly sensitive to the adverse health effect of ground-level ozone exposure, sulfur dioxide, nitrogen dioxide, and carbon monoxide.  

Smog can cause you damage to your health and lungs – even when you can’t see or smell it in the air around you. It can inflame breathing passages, decrease the lungs’ working capacity, can cause shortness of breath, pain when inhaling deeply, wheezing, and coughing. Long term exposure to air pollution can cause chronic health concerns, such as cancer and damage to the body’s immune, neurological, reproductive, and respiratory systems.

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Smog is made of a combination of air pollutants that are too small to see by a naked eye. However, tis tiny particles are big contributors that compromise human health, harm the environment, and even cause property damage; all we need is to protect our health against all these potential harm. Smog often begins in big cities by which air pollution emitted by vehicles, energy consumption, population, carbon dioxide emission, and aggregate emissions causes pollution to the air we breathe.

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The Somatic Mutation Theory of Aging is one of several well developed theories that attempt to explain why human bodies age. Logically, it does not make sense that the same body that produces billions of cells from the age of 0 to about 27 suddenly begins to loose the ability to produce new cells that are as vital and strong as they have always been. The mechanism of reproduction does not change. The general cellular structure does not change. For the most part, the vast majority of your cells continue to do this quite well for another 20 or 30 years. But, everyone eventually knows that the aging process catches up with them.

The simple idea behind a complex theory is that with the tens of thousands of genes that are reproduced every time a cell in your body divides to make a new cell, an occasional error happens. Most of these incorrectly copied genes never create any problems. However, without being repaired, later copies make the problem worse. Eventually, the line of cells coming from the errant copy no longer quite function like the original cell. This process happens over and over and over during a span of several decades until enough poorly functioning cells are present to cause changes in the tissue that they comprise. The outcome is called aging.

With comic books and movies like the X-Men, people tend to view a mutation as a new and superior life form. However, almost all mutations change the cell or organism downward rather than upward. This means that in nearly every case, when a cell mutates, the copy is not as good as the original. Once the step downward occurs, it is all but impossible to reverse. People try to do this artificially with vitamins, skin creams, and plastic surgery. All of these techniques only mask the marching of aging.

This could be a skin cell, liver cell, stomach cell, or almost any other cell in your body. Because people tend to live longer today than they have lived historically, more of the aging process becomes visible. Wrinkles and lines are indicators that lower quality skin cells are being produced in higher quantities. Because the skin is exposed to more destructive environmental factors than the internal organs, it shows the effects of the somatic mutation sooner.

As people live beyond 90 and 100 years, more of them die from multiple organ failure due to aging. The lungs, heart, liver, kidneys, muscles, and every other organ suffers from the effects of long term somatic mutation. Just as the skin sags and wrinkles, the other organs have their way of showing the loss of function from aging. Kidneys either quit working altogether or they dump more than necessary of the bodies nutrients into the urine. Lungs loose their elasticity and fill with fluid. The heart becomes weaker and cannot maintain adequate blood pressure to keep other organs functioning correctly. The list goes on.

Weak lungs put pressure on the heart. This causes an aging heart to attempt to build itself bigger and stronger and in so doing, it produces more mutated cells. The same scenario can play out throughout the body until the mutations become some prevalent that survival is impossible.

Reference:

http://longevity.about.com/od/longevity101/a/why_we_age.htm

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The cardiovascular is perhaps the most amazing system of the human body. It hosts one of the most precious fluid in the world- the blood.The blood transports oxygen and nutrients to the three hundred trillion cells in our body, thus supplying them with life sustaining fuel and energy. It also removes the waste from these cells, thus preventing them from dying from toxic suffocation. It fights and destroys harmful pathogens that may invade the body, and it protects the body own cells. It is indeed the fluid of life, functioning with the aid of yet another marvel – the fascinating cardiovascular system.

What is the cardiovascular system?

It consists of the heart; and its related circulatory systems; the blood; the blood vessels; and the pulse / pressure.

The Heart and its location

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The heart is the pump that supplies the power to maintain the circulatory systems of the body. It lies in a part of the chest called the thoracic cavity: between the right and left lungs and a little above the diaphragm.

THE STRUCTURE OF THE HEART

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The heart is divided into four chambers: The right atrium and left the atrium;  and the right ventricle and the left ventricle. Internally, each atrium is divided by a partition called interatrial septum, and each ventricle is divided by the interventricular septum. There are two additional partitions called the Tricuspid valve and the Mitral valve, and these control the flow of blood inside the heart. The tricuspid valve allows blood to flow downward from the left atrium into the left ventricle and inhibits a backflow from returning to the atrium, and the mitral valve functions in a similar way between the right atrium and the right ventricle.

The Pulmonary and Systemic Circulation

What is the pulmonary circulation?

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It is the circulation of deoxygenated blood moving from the heart to the lungs.

Two large veins, called the superior and inferior venae cavae, collect deoxygenated blood from the upper and lower parts of the body and pump it into the right atrium. This passes through the atrium by the way of the mitral valve: and the valve allows the blood to pass through without flowing backwards, under normal healthy conditions. The blood enters the right ventricle, and is taken by the pulmonary artery to the lungs where it exchanges its carbon content for oxygen.

What is the systemic circulation?

It is the circulation of oxygenated blood moving from the lungs to the heart and then to the whole body.

Four pulmonary veins take oxygenated blood from the lungs and carry it to the heart – then pour it into the left atrium. From there, it forges through the tricuspid valve into the left ventricle. It is then pumped through the aorta- the largest artery, and from there it is routed and dispensed to all the other organs, tissues and cells except for those of the lungs.

The Coronary Circulation: http://kidshealth.org/image/ial/

WHAT IS THE CORONARY CIRCULATION?

It is the circulation designed for the muscles of the heart.

Why does the heart have its own circulation?

Because of the thickness and the fiber-like structure of the myocardium – heart muscle, it is unable to extract sufficient nutrients from the blood passing through, to fortify itself. Thus it must rely fully on the coronary circulation, which becomes its blood lifeline. Arising from the base of the aorta are two arteries: the right and left coronary arteries. The left coronary artery, branches to the left, and splits into two major parts called the anterior interventricular artery and the circumflex artery. The former of these two arteries supplies blood to the inner walls of both ventricles; while the latter supplies to the left atrium and the rear sections of the walls of the left ventricle. The right coronary artery branches to the right and like its left partner, it splits into two parts. These are the posterior interventricular artery and the marginal artery. The former of these two arteries supplies blood to the rear sections of the ventricular walls of the heart. But together, both supply the right atrium and a large portion of the right ventricle.

The Blood: Its Structure and components

The blood is comprised of the Red Blood Cells, The White Blood Cells, The Blood Platelets, and Plasma.

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The Red Blood Cells - also called erythrocytes, are small in size, and biconcave in shape. Their size and shape are maintained and supported by a large group of proteins. One of these proteins called Spectrin has elastic-like properties, and this allows the red blood cell a great deal of flexibility. They are able to change shape when entering tiny capillaries that are smaller in diameter then themselves: and then resume their original shape when they return to the larger vessels. Another protein – hemoglobin gives the red blood cells the capacity to transport oxygen throughout the body in a very efficient manner. Hemoglobin is comprised of two proteins – globin and heme, a red pigment that gives the blood its red coloring. One molecule of heme contains one atom of iron, and that allows it to attach, and combine itself with oxygen. The red blood cells are formed in the red bone morrow and have a lifespan of one hundred and twenty days. At death they are transported to the liver and spleen where they are broken down, and the iron component is recycled – used to make more hemoglobin for the formation of new red blood cells.

Red and White Cells

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The White Blood Cells - also called leukocytes, are the disease fighters of the body. They are classified into five types and can be describes as follows:

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The Blood Platelets – also called thrombocytes, are the smallest of the bloodcells.                    Technically, they are not really a cell in that they have no nucleus; but paradoxically they Function as such. Structurally, they are made from the fragments of very large cells called megakaryocytes. These large cells are encased in the bone morrow, but pinched bits of themselves off, and release these in the blood stream where they function as platelets. The platelets are the clotting agents for the blood. They repair ruptured vessels by forming a protective clotting seal made from a large variety of different chemicals.

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The Blood Plasma: This is the liquid portion that is used to convey all of the other blood cells. It consists of ninety percent water, seven percent proteins including (1) globulins, (2) albumins (3) fibrinogens. The remaining three percent of plasma consists of glucose, fats, bile, and electrolytes.

The protein components have clotting properties, and they assist the platelets with the job of repairing ruptured blood vessels by forming more seal to accelerate the process.

The Blood Vessels

The blood vessels are the cardiovascular transportation system. They are divided into three main Groups: (1) arteries, and arterioles; (2) capillaries; (3) veins, and venules.

The Arteries: These are large vessels carrying blood away from the heart. Their walls are spacious and lined three layers of tissues:

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1. an innermost layer – tunica intima; 2. A middle layer; – tunica media; and 3, An outer layer – tunica externa. The lining of the these layers are coated with the rubber- like protein, elastin that enable them to push the blood with sufficient force so that it can reach the extremities of the body. Elastin also allows the arteries the flexibility to expand without rupturing, and absorb the pressure from the forceful blood as it leaves the heart. The walls of the arteries are also lined with sensor – like fibers. These sensors help to further regulate and direct the flow of blood even as it is propelled into the smaller branches – the arterioles. The arterioles are really small arteries with diameter a little larger than the capillaries. They function as small tributaries, conveying blood into territories too minute for the large arteries

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The capillaries: These are the tiniest of the blood vessels. Their small size and thin walls allow them the capacity to convey blood, and supply nutrients to the small tissues and cells; while they simultaneously collect the waste products from these cells and deposit them back into the blood stream. There are three basic types of capillaries. (1) Continuous Capillaries, (2) Fenestrated Capillaries; (3) Sinusoidal Capillaries. Continuous capillaries are most commonly found in the skin and muscles. Their endothelial cells – cells in the lining of their walls are closely connected, to prevent interruptions within the connective tissues. Fenestrated capillaries are almost like the continuous, but are covered by a delicate membrane, rendering them more permeable to fluids. Sinusoidal capillaries– also called leaky capillaries, are located in the liver. Their endothelial linings are more relaxed and allow large molecules and cells like the killer white T cells to pass from the blood into the tissues.

A vein with its lumen http://upload.wikimedia.org/wikipedia/commons

inferior venacava

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Veins: Veins are large vessels like the arteries, yet they are different in many ways. So in what ways are they different? They differ in the way they function.

Primarily, they function as carriers of deoxygenated blood. But in the pulmonary circulation described earlier, the four veins carrying the blood from the lungs back to the heart, do just the opposite – they convey oxygenated blood. Their walls consist of three layers like that of the arteries, but they are thinner and have less elastic properties. Consequently, they offer less resistance to the flow of blood.

Pulse And Blood Pressure

What is the Pulse?

The rhythmic expansion and contraction of the arteries as the blood gushes through, leaves them with the marked impression called the pulse. The rhythm of the pulse, which can be felt at the different pulse points on the body, synchronizes with that of the heart; thus, leaving the typical healthy adult with a pulse of 60 to 100 beats per minute.

How is the blood pressure different from the pulse?

Blood pressure is the force exerted on the walls of the arteries as the

flow of blood passes through them. The myocardium  (the heart muscle), contracts and relaxes to build up the force needed to channel the flow of blood through the heart, and this contraction creates rising pressure. When the rising pressure reaches its maximum intensity on the atrial side of the heart, the atrioventricular valve is opened and the blood gushes into the ventricle. The high-pressure periods used to force blood movement are followed by low-pressure periods of relaxation. These periods are known as systole and diastole. One complete heart -beat consists of one atrial systole and diastole, plus one ventricular systole and diastole.

How are the systolic and diastolic pressure measured and interpreted in blood pressure tests?

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The blood pressure is measured using an inflatable instrument called “sphygmomanometer” (blood – pressure cuff), joined to a device; and also a stethoscope. The blood pressure cuff is wrapped around the upper arm and inflated to stop the flow of blood to the vessels. It is then deflated gradually, and the doctor uses the stethoscope to listen to the sound made by the blood as it moves through the artery. The reading is given in two numbers that are recorded in millimeters of mercury. The standard reading of 120 mm Hg / 80 mm Hg, means that the force exerted on the walls of the arteries when the heart is in systole; is equivalent to the pressure from a column of mercury that has a height of 120 mm. When it is in diastole, the exerted force is equivalent to the pressure from a column of mercury with a height of 80mm.

Readings found during three consecutive tests to exceed the standard of 120mm Hg / 80mm Hg, are classified as cases of hypertension or pre-hypertension.

Hypertension is the leading cause of stroke, and it plays a big role in the triggering of heart attack. Although it is usually linked to genetic factors, and the age, sex, and weight of the person; it is also known to strike males and females alike.  It has also struck people of different races, and different ages as seen in the cases of  childhood obesity in recent years. In 2007, The American Medical Association reported that the increase in childhood obesity has led to an increase in the rate of hypertension in children.

Hypertension is called a silent killer, because in its mild and moderate forms, it often presents no symptoms. Hence in the absence of the symptoms, a person could have hypertension for months, perhaps for years without knowing it. This puts him / her at risk for developing one of the more chronic forms of heart diseases.

It is therefore imperative that we keep our blood pressure in check. Eat healthy foods in moderation and in the right combination that will make up a well balanced diet; avoid excessive drinking of alcoholic drinks and beverages to protect the keepers of your body. Wonderful cardiovascular system.

More articles on human health and the human body

http://healthmad.com/aging/extremely-exciting-new-revelation-about-our-memory-and-the-aging-process-twenty-five-fantastic-ways-to-preserve-it/

http://www.ehow.com/how_4988324_boost-up-memory.html

http://www.ehow.com/how_5131839_exercise-cells-achieve-better-memory.html

http://scienceray.com/biology/human-biology/the-incredible-human-genome-project-brilliant-stem-cell-research-the-marvelous-promise-to-cure-degenerative-diseases-and-genetic-disorders/

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Hair comes in all colours, lengths, and thicknesses and it can be straight, slightly kinked, or very curly. Hair type is mostly determined by genetics, whether it is of animal, or human origin.

Geneticists have discovered that some physical characteristics of human hair are dominant, which means that they are more likely to be passed on to children. The characteristics that are less likely to be passed on are called recessive.

Dominant characteristics include curly hair, dark hair, non-red hair and recessive characteristics include straight hair, light hair, and red hair.

So a child is more likely to inherit dark, curly hair from either parent than straight, light coloured, or red hair from either parent. Obviously, if both parents have any of these characteristics the odds of inheritance become much higher.

Both men and women have a total of around 5 million hairs on their bodies. These may be dark and easy to see, or so fine that it is difficult to see them with the human eye. Even bald-headed people have minute hairs on their heads.

Fair-haired people tend to have slightly more than the average and redheads slightly fewer. The only parts of the human body that are totally hairless are the lips, the palms of the hands, the soles of the feet, the sides of the toes and fingers and the upper part of of the ends of fingers and toes.

Hairs are dead from the root upwards but the 100,000 or so hairs on the head grow at a rate of 10mm, or 0.4 inches per month with a slight increase during the summer months. That’s an amazing 4.8 inches per year.

Contrary to popular belief, cutting hair does not make it grow faster, or slow it down. Thickness varies according to hair colour and redheads have thicker hair than brunettes and blondes.

Most people lose and replace about 100 hairs per day, but hairs can remain in the same follicle for up to six years.

Stories are often told about people finding that their hair has turned white over night when they have had a fright, or sudden shock. This is not true and what happens in these cases is that the coloured hair actually falls out and it leaves the white hair behind. The person may not know that they had any white hair before because it is often hidden by the coloured hair.

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Medical examiners use various methods of determining the approximate time of death of their patients. Approximate time of death can provide a foundation for which to build a timeline of a person’s death. Doing so assists in the investigative process.

1. Livor mortis, or lividity. When a person’s heart stops beating, his or her blood settles to the lowest points of gravity. If he’s laying on his back, the blood will settle in his back, buttocks, back of the neck, etc. Approximately 20 minutes after death, the skin in these areas start to change color as a result of the blood pool. The skin will turn a purplish/pinkish/brownish/reddish (it really varies, especially by skin color). Four to eight hours after death, depending on various factors such as weight, temperature of the room, medical history, medications etc, the lividity will become “fixed” and it will no longer be possible to “move” the lividity by rolling the person over, or by pressing the skin with a finger. When lividity is not set, pressing into the skin with a finger will turn the skin a white color, and then it will turn back. Similar to what happens when you press down on your fingernails.
2. Rigor mortis. This is the infamous stiffening of the joints after death, due to metabolic acid build up. Rigor starts forming between 1-2 hours after death, maximizes at 12 hours after death (complete stiffness), holds for another 12 hours, and then goes away over 12 hours. In short: it lasts 36 hours. The “degree” of rigor, or how stiff the person is, can assist in determining how long the person has been dead. If he or she is in full rigor (there’s no way to move their joints), you will know they have been dead for approximately 12-24 hours.
3. Family statements. The family saying things such as “I last saw him before bed, at X:XX PM” can provide a basis for which to determine approximate time of death.
4. Clues around the house. The state of the house, especially when a person is already decomposed, can provide helpful information.

The following are just a few environmental clues that can assist in determining time of death:

1. The decedent having five days worth of mail built up
2. No electricity in the house
3. Dust build up on everyday things, such as the sink, toilet, fridge, etc

While time of death can only be calculated as an estimation, it is still a vital tool in investigating suspicious deaths.