Do you know why people go bald?

Prof. Know Why explains:

Normally, there are about 100,000 to 150,000 hair strands on the human scalp. However many people cannot retain them and eventually go bald.

Androgenetic Alopecia, the most common type of baldness — otherwise known as male pattern baldness — occurs due to a chemical known as Dihydrotestosterone (DHT) that builds up around the follicle and eventually kills the follicle and the hair. In simple terms, the growing cycle becomes shorter. So the hair does not grow as long as it once did. It becomes finer, and eventually the growth cycle is eliminated.

A follicle’s resistance to DHT is genetic – which is why some people go bald and others do not. If you have relatives with thin hair or who are bald, you may well develop the same problem. Doctors say that the gene can be inherited from either the mother’s or the father’s side of the family and skips generations.

In other conditions, such as Alopecia Totalis and Alopecia Universalis, the entire scalp and entire body become completely bald due to a viral condition.

Patch baldness, in which hair falls out of the scalp in patches, is caused by stress or poor nutrition or adverse scalp conditions. In this case, the hair usually grow back once the cause has been rectified.

While the effects of hair loss can be devastating, there are treatment options from non-surgical techniques to hair transplants that can slow or stop hair loss or even gain the appearance of a full head of hair. So just don't worry too much and be happy!

Do you know why trees shed leaves?

Prof. Know Why explains:

Like people, the leaves of trees also age, but do so much more rapidly. Each spring the young leaves develop from buds and then rapidly mature to full size to carry on photosynthesis (the process that provides food needed for the tree to grow and maintain itself). By autumn, the leaves of many hardwood trees reach old age and do not function well. At this time a tree must also prepare for the harsher weather conditions of winter. Signals to the tree indicating it is time to prepare for winter include shorter days, less intense sunlight and cooler temperatures. Prior to the leaves falling, nutrients like nitrogen and phosphorus move from the leaf into the adjacent stem to be reused during the next growing season. The following spring a new crop of leaves are produced and the cycle is repeated.

To sum up, in early autumn, in response to the shortening days and declining intensity of sunlight, leaves begin the processes leading up to their fall. The veins that carry fluids into and out of the leaf gradually close off, as a layer of cells forms at the base of each leaf. Once this separation layer is complete and the connecting tissues are sealed off, the leaf is ready to fall.

Thus while trees can live for decades and even centuries, some parts of the tree like the leaves, live for only a few months or years (in certain varieties of trees).

Do you know why lizards lose their tails?

Prof. Know Why explains:

Lizards can lose their tails, but not all lizards can grow them back, though. Lizards that lose their tails also lose an important source of energy because they store fats at the base of their tails.

In lizards, the tail bones have central regions that break away easily when the tail is pulled. The muscles of the tail pull apart and the blood vessels constrict to stop the wounded tail from bleeding. So, if a predator attacks a lizard, the tail is designed such that it separates from the body allowing the lizard to escape while the predator gets the tail. Lizards that lose their tails grow them back but the replacement tail is never as long or as colorful as the original one. Replacement tails grow back in as little as three months or as long as two years.

In short, in order to defend it in a threatening situation, the lizard chooses to detach its tail by contracting a special muscle near a weakness in its vertebrae.

In lizards, especially big ones like Iguanas and Komodo Dragons, the tail bones are not designed to break easily and the tail muscles are also not designed to pull apart smoothly. These lizards however can also lose their tails, but it takes a much stronger pull to make this happen. With these types of lizards, the wound heals like others though, but the tail does not grow back.

Do you know why we cry?

Prof. Know Why explains:

Women cry 64 times a year on average, while men just 17, says a recent study. Actors and politicians do it on demand though! But why does crying happen in the first place?

When we become upset, our brains and bodies overreact and work overtime, producing chemicals and hormones. Crying helps eliminate t,hese extra chemicals that we don't need, in the form of tears. These tears are formed in tiny glands present in the upper eyelids of our eyes, called lachrymal glands.

Scientifically, emotional tears contain high levels of manganese and a chemical called prolactin.

As our tears flow, they sooth our sadness or distress by disposing of these chemical agents. That is why generally, we feel calmer or more refreshed after crying, because the tears get rid of these hormones that are produced when we are sad, happy, or distressed.

Do you know why people snore?

Prof. Know Why explains:

This is one of the most common problems worldwide. Snoring occurs when the muscles at the back of the throat relax during sleep and narrow the passage through which you breathe. As the air passes through this narrowing, the soft palate and uvula vibrate and produce the sound of snoring. The airway can be further narrowed due to:

- Poor muscle tone (after alcohol or sedative use).
- Enlarged tonsils and adenoids.
- A long soft palate or uvula.
- Blocked nasal airways from polyps, a deviated septum, allergies or a cold.
- Excessive weight causing tissue at the neck to be bulky and flaccid.
- Tissue swelling from cigarette smoking.
- Hypothyroidism.

However, snoring can be treated medically.

Somnoplasty is a new technique to treat snoring painlessly. It involves placing an electrode for a brief moment into the soft palate to locally reduce the quantity of tissue. As it heals over the next few weeks and the soft palate shortens and stiffens, the vibration of the soft palate decreases and snoring is eliminated.

In selected cases, laser treatment is the best choice. It is done using a high-intensity laser beam to trim and reshape the uvula and soft palate.

Wearing a dental appliance at night can also offer another solution. Molded to the teeth, this appliance keeps the lower jaw in a forward position during your sleep therefore decreasing your snoring. This appliance is often used to treat obstructive sleep apnea.

Do you know why camels survive without water?

Prof. Know Why explains:

The humps on a camel's back are actually huge heaps of fat and flesh that can weigh as much as 80 pounds in a healthy camel. These humps help camels survive for weeks without food and water.

When water and food become scarce in the deserts where camels roam, the fatty humps serve as stored food and are used for nourishment. As the camel's body metabolizes or uses up the humps' stored fat, the hump becomes smaller and flabbier. So the longer the camel goes without eating, the smaller its hump gets. The size of a camel's hump helps determine a camel's health, food sources, and overall well-being.

These humps, or reserves of fat, are the reason why camels can go for days without water and food. While humans are supposed to drink 8 glasses of water a day, camels can go without water for nearly 2 weeks!

Do you know why we have gallstones?

Prof. Know Why explains:

In medicine, gallstones (choleliths) are crystalline bodies formed within the body by accretion or concretion of normal or abnormal bile components. In easier words, they are small, hard, pathological concretions, composed chiefly of cholesterol, calcium salts, and bile pigments, formed in the gallbladder or in a bile duct.

Researchers believe that gallstones may be caused by a combination of factors, including inherited body chemistry, body weight, gallbladder motility (movement), and perhaps diet.

Cholesterol gallstones develop when bile contains too much cholesterol and not enough bile salts. Besides a high concentration of cholesterol, two other factors seem to be important in causing gallstones. The first is how often and how well the gallbladder contracts. Incomplete and infrequent emptying of the gallbladder may cause the bile to become over concentrated and contribute to gallstone formation. The second factor is the presence of proteins in the liver and bile that either promote or inhibit cholesterol crystallization into gallstones. In addition, increased levels of the hormone estrogen as a result of pregnancy, hormone therapy, or the use of birth control pills, may increase cholesterol levels in bile and also decrease gallbladder movement, resulting in gallstone formation.

Low-fiber, high-cholesterol diets, and diets high in starchy foods are suggested as contributing factors to gallstone formation. Other nutritional factors that may increase risk of gallstones include rapid weight loss, constipation, eating fewer meals per day, eating less fish, and low intakes of the nutrients folate, magnesium, calcium, and vitamin C.

On the other hand, coffee, wine, fish, and whole grain bread may decrease the risk of gallstones.

Do you know why onions make us cry?

Prof. Know Why explains:

It is not the strong odor of the onion, but the gas that the onion releases when we peel off this member of the lily family, makes us cry.

The onion itself contains oil, which contains sulfur, an irritant to both our noses and to our eyes. Cutting an onion arouses a gas contained within the onion, propanethiol S-oxide, which then couples with the enzymes in the onion to emit a passive sulfur compound. When this upwardly mobile gas encounters the water produced by the tear ducts in our eyelids, it produces sulfuric acid. In response to the caustic acid, our eyes automatically blink due to irritation and produce tears to flush out the sulfuric acid.

Moreover, to rid the eyes of this foreign substance, we instinctively rub our eyes with our hands, while into the act, which again exacerbates the situation, as our hands are coated with the caustic, sulfuric acid producing oil from cutting the onion.

The only remedy to get rid of this pungent, irritating oil of the onion is to boil it, and not to slice it or dice it.

Do you know why the sky is blue?

Prof. Know Why explains:

The atoms of nitrogen and oxygen in the atmosphere separate the sun’s white light into its many colors and scatter them throughout the atmosphere. The wavelength of the blue light scatters better than the rest, predominating over other colors in the light spectrum. This makes the sky appear blue to us on a clear day.

The scientific name for this phenomenon is ‘Tyndall Effect’, more commonly known as ‘Rayleigh Scattering’. This phenomenon describes the way in which light physically scatters, when it passes through particles in the earths atmosphere that are 1/10th in diameter of the color of light. The light spectrum ranges in wavelength from red to violet and since the wavelength of the blue light passes through the particles with greater ease than the wavelengths of other colors of light, the sky appears blue to the naked eye.

The human eye has three types of light receptors, known as cones, located in the retina. The cones are either considered to be red or blue or green, based upon their strong response to light at these wavelengths. As light stimulates these receptors, our vision translates the signals into the colors we see. The skylight stimulates the red and green cones almost equally, while stimulating the blue cones more strongly, resulting in the blue colour of the sky.

Do you know why dogs bury bones?

Prof. Know Why explains:

Dogs generally do this, trying to save excess food in case there’s a scarcity. Though most of them don’t need to do so being domestic pets, the trait had been actually handed down to them by their ascendants – the wild species of dogs.

This pattern is quite common among the predators in the wild who tend to return to their saved food for future meals. But animals, unfortunately being without etiquettes, never keep away from other’s table (or dish). Thus, hyenas, jackals, vultures and other scavengers (and not to forget their own species) always remain uncalled visitors to the predator’s unfinished prey. As a result the need to hide the left-over arose, giving birth to animal-intelligence of hiding the remains from the public glare. The concept followed and they would bury their food.

Scientists say that most dogs do this out of instinct. As is said, domestic dogs are descendants of wild wolves, who often used to come back to their left over food when they were hungry again.

But, on a lighter note, if one fine day, you find your dog burying a bone, it could simply mean that he has more than enough to eat.