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 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 Bush winked at the Queen?

Miss Finder –The Journo, investigates:

When you've just made it sound like the Queen is more than 200 years old, there could be only one way of recovering from the gaffe. That’s typically the Bush’s self-proclaimed way of projecting smartness, after a blundering stupid act. Yes! Turning to her and giving her a sly wink which might not necessarily needed to be included in any book of royal etiquette though. That's exactly what happened on 7^th of May, 2007 after George Bush mangled his greeting to the Queen on her state visit to the U.S.

Stumbling over his words, he came perilously close to suggesting that the monarch had toured the States in 1776. And although the President's following wink was initially rewarded with a regal glare, the Queen did at least seem to see the funny side of the blunder.

Being human, it was only a forgivable slip-of-tongue-issue, though not expected, which could have been rectified with a normal and humble ‘sorry’, instead.

But may be that the president, without finding any other form of expression, resorted to his impulsive cowboy-type street smartness!

Any comments guys?

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 we laugh?

Prof. Know Why explains:

The reasons we laugh, including ‘contagious’ laughter, may be products of evolution. Natural laughter is a two-part, spontaneous, response to humor, that has physiological, psychological, and physical benefits. Most agree that we laugh when we find something to be humorous, though different reasons exist for what we find to be humorous. Additionally, different things are humorous to us at different stages of life.

Laughter, a physiological response to humor, can be broken down into two parts. The first is a set of gestures, and the second is the production of sound. The brain forces to conduct both responses simultaneously.

From a physiological standpoint, a ‘sensor’ in the brain responds to laughter by triggering other neural circuits in the brain, which, in turn, generate more laughter. Oddly enough, laughter is an orderly response, and almost occurs spontaneously during pauses at the end of phrases, earning it the name the ‘punctuation effect’. Human beings are the only species capable of laughter, and an average adult does so approximately 17 times per day.

Scientists say that laughing is a great exercise and estimates that laughing 100 times is equivalent to a 10-minute workout on a rowing machine, or 15 minutes on a stationary exercise bike.

Do you know why pregnant women crave for pickles and ice cream?

Prof. Know Why explains:

Pregnant women are famous for their midnight yearnings for pickles and ice cream. And the desire for chocolates is the stuff of legend.

It’s tempting to believe –as many people do –that cravings are the body’s way of telling us that we are lacking a certain nutrient which the food we crave can supply. Chocolates, as the belief goes, might soothe a broken heart by replacing compounds lost in oceans of tears. But pregnant women might crave ice cream because they need calcium and pickles because they lack sodium.

Pregnant women rarely crave for fruits and vegetables. More often, they yarn for foods that are very sweet, spicy or salty. From an evolutionary standpoint, this makes sense. A craving for highly palatable foods may have been nature’s way of boosting calorie intake, ensuring a healthy pregnancy.

So would-be fathers –get ready for your sweet-heart’s sudden demand of a chocolate-ice cream in the wee hours of the night.

Do you know why stars twinkle?

Prof. Know Why explains:

On a clear, dark night, our eyes can see about 6,000 or so stars in the sky. They seem to twinkle, or change their brightness, all the time. The scientific name for this twinkling of stars is stellar scintillation or astronomical scintillation. Stars seem to twinkle when we see them from the Earth's surface, because we are viewing them through thick layers of turbulent (moving) air in the Earth’s atmosphere.

The Earth's atmosphere comprises of layers of gases surrounding the Earth. It’s composed of 78% nitrogen, 21% oxygen, 0.9% argon, 0.03% carbon dioxide, and other gases. These gaseous layers insulate the Earth from extreme temperatures and block the Earth from much of the Sun’s incoming ultraviolet radiation.

As light of a star travels through these layers of the Earth's atmosphere, it is bent or refracted many times and in random directions (it happens whenever it hits a change in density - like a pocket of cold air or hot air). This random refraction results in the star appear to our eyes as twinkling.

Stars would not appear to twinkle if viewed from outer space or from a planet that doesn't have an atmosphere.

Do you know why we suffer from blocked ears?

Prof. Know Why explains:

While travelling by aeroplane or climbing mountains we might have temporary ear blockage, which is not associated with loss of hearing though. This happens due to an imbalance in air pressure. Let’s see how it happens.

Ear comprises of three parts –external, middle and internal ear. And for normal hearing, we need to have proper air balance in the middle as well as the external ear. The ‘hearing mechanism’ works like this: A membrane called Tympanic membrane separates the middle ear from the external ear. The middle ear is connected with the upper part of the Pharynx by a tube called the Eustachian tube. Now, when we breathe in, a portion of the air enters the middle ear through this tube. So to balance the pressure within the ear for normal hearing, some amount of air also enters the external ear through the external auditory canal.

But when in a flight or on higher altitudes, the atmospheric pressure inside the middle ear remains the same, while that on the outside reduces, resulting in a pressure imbalance causing temporary ear blockage.

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.