Q & A - QUESTIONS AND ANSWERS
 |
| QUESTIONS AND ANSWERS |
1. WHAT MAKES A PERSON GOOD-LOOKING?
Certain people are deemed by society to be good-looking. Although beauty is in the eye of the beholder, studies show that some universal factors contribute to physical beauty.One of the most important factors of beauty is symmetry. A face that is perfectly symmetrical is generally found to be good-looking. Symmetry is a sign of health and a sign that the person is free from disease or deformity. A so-called golden ratio has been discovered, whereby the various aspects of the face in good-looking people accord to the ratio of 1:1.618, which promotes symmetry. If the face has these proportions, it will usually be considered attractive. Similarly, bodily proportions play a role, with a hip-to-waist ratio in women of 0.7 (where the waist circumference is 70 percent of the hips) considered ideal. The proportion of body mass to body structure is another important determinant for both sexes. For both men and women, pronounced cheekbones and a strong jaw are also appealing as signs of health and strength. A clear and healthy complexion is also found attractive.
Most other universal beauty indicators also relate to health and the ability to provide strong offspring. In men, an erect posture, a wide chest, and a greater-than-average height are important because they indicate physical strength (and an ability to produce and protect healthy offspring) and confidence. Well-defined muscles and some body hair are also often appealing to women, as they are signs of testosterone and masculinity. In women, a youthful appearance is important, and long fingernails and hair can also be signs of beauty. These attributes are thought to indicate health. Vivid lips, large eyes, dimples, and white teeth are also signs of health and beauty in women.
2.WHAT IS THE DIFFERENCE BETWEEN HARD AND SOFT WATER?
Soft water is water that contains low levels of minerals. Generally speaking, rainwater is naturally soft. As it permeates the ground and enters water reservoirs, it picks up various minerals, making it hard. Although hard water contains other metals, it usually has high levels of the metal ions calcium and magnesium.
Soft water increases the effectiveness of soaps and detergents. When mixed with soft water, soap provides a rich and creamy lather not found when it is mixed with hard water. Soft water is far more efficient than hard water and requires less soap. Cleaning with soap and soft water is also faster because the metal ions in hard water form insoluble salts, resulting in scum. The cleaning difficulties associated with hard water are the reason for its name. Soft water also results in far fewer limescale deposits in household items such as kettles and washing machines.
Despite its inconvenience for cleaning, hard water contains essential minerals and is considered better for drinking. Some studies show a reduced level of heart disease in men who drink hard water. The calcium in hard water is also beneficial for teeth. The minerals alter the flavor of the hard water, making it more palatable. For this reason, hard water is used to make certain beers and whiskeys. The minerals in some hard waters also stop corrosion and can help prevent damage to underground pipes.
Some water can be softened by filtration or by reducing the mineral levels through other means. Boiling can soften water if its (temporary) hardness is caused only by bicarbonate ions.
3. HOW AND WHY DO CHAMELEON LIZARDS CHANGE COLOR?
The chameleon is a small lizard, found mainly
in Africa and Madagascar (but also parts of Europe and Asia), that is
famous for being able to change its color.
Most people believe that the chameleon changes
color as a means of camouflage it blends in with its surroundings.
Not true. The lizard changes color depending on its physical or
emotional disposition at the time. Chameleons change color in response
to changes in light and temperature. The change of colors also depends
on the mood of the lizard and plays a major role in communication with
other chameleons. Their colors range from brown and green to red, blue,
and yellow. Coincidentally, brown and green often match the
chameleon's background, which leads people to think that camouflage is
the reason for the change.
In cold conditions, a chameleon will turn a
darker color to absorb more heat, and in hot and bright conditions, a
chameleon will turn a lighter color to reflect the heat. To attract a
mate, a male chameleon will exhibit his brightest and most impressive
colors. If a rival male approaches, he will turn a bright color, such as
red, indicating that he is a healthy specimen and ready to fight. If a
chameleon is scared, it will often turn a dark color.
Chameleons are able to change colors because
of their unusual genetics. Special cells lie in layers beneath their
transparent skin. The upper layer contains red and yellow pigments,
while the lower layer contains a colorless substance that reflects the
blue part of light. Under these cells is a dark layer of melanin. This
melanin influences how light or dark the reflected light is. Depending
on the temperature, the brightness, or the chameleon's mood, hormones
trigger the chameleon's brain to send a signal to activate particular
cells. This message tells the cells to expand or contract,
redistributing their colors and creating a different overall color for
the lizard.
For example, if the upper cells are yellow and the lower
cells reflect the blue part of light, the colors mix and the chameleon
turns green. The result of this unique chemistry is a lizard that can
produce a wide variety of different colors to suit its circumstances.
HOW TO PASS LABORATORY EXAMS
4. WHAT ARE THE HEALTH RISKS OF CELL PHONES?
Since the massive increase of cell phone use
in recent years, health concerns have been raised, in particular whether
they cause brain tumors. This has resulted in extensive research on
both animals and people.
Cell phones use electromagnetic waves in the
microwave range. Some of these waves can be absorbed into the human
head. Microwaves are known to produce dielectric heating, in which
living tissue is heated. With cell phone use, this results in the
temperature of the head increasing slightly. Some experts suggest that
cell phone use may lead to brain tumors, although others say that the
brain easily disposes of excess heat by regulating its blood
circulation.
It is also thought that the levels of
radiation emitted by cell phones damage the blood-brain barrier, which
prevents harmful substances from entering the brain. Some studies have
shown that the radiation causes the cells in blood vessels to shrink,
allowing molecules to pass into the brain tissue. A 2004 study found
evidence of DNA damage to cells, as well as gene and chromosome damage,
and an increased rate of cell division (often associated with certain
types of cancer). A more recent study from a Swedish team suggests that
the radiation emitted causes damage to nerve fibers, potentially
resulting in brain tumors. The study says that a person would probably
have to use a cell phone for more than 10 years to be at risk.
5. HOW DO FISH BREATHE?
Although whales and dolphins have lungs that store air, which they breathe from the surface, fish don't have lungs. Instead, they have evolved to breathe underwater.Water contains a small percentage of dissolved oxygen. Fish use their gills to concentrate the oxygen and absorb it. Water flows into the fish's mouth and through the gills. The oxygen in the water passes into the blood-enriched gill structures called filaments and lamellae. The latter are thin, disk-shaped membranes that are filled with a dense capillary network. As the oxygen is absorbed, the carbon dioxide in the fish's bloodstream passes into the water and is removed from the body. There is essentially an exchange of oxygen and carbon dioxide across the capillary membrane. As water is pumped in and out of a fish's mouth, the fish is, in effect, breathing.
The gills have a large surface area to aid in the absorption of the oxygen. But the gills need to be immersed in water to support their weight. If a fish is on land, the gills collapse and the filaments stick to one another. Very little surface area is exposed to absorb oxygen, and this leads to a fish out of water lacking the oxygen it needs and consequently suffocating.
6. IS THE HUMAN BODY REALLY 80 PERCENT WATER?
It is often stated in health magazines that 80 percent of the human body is water. But is this actually true?
The human body depends on water. The amount of fluids in the body strongly influences a person's well-being. Although the exact percentage of water varies, depending on what source is quoted, scientists believe that we are in fact made up of around 72 percent water and 8 percent chemical compounds. The remaining 20 percent is bone and solid tissue. The water actually contains sodium chloride (salt) and potassium chloride, and about two-thirds of it is in our cells. The rest is free-flowing liquid in the form of blood plasma and liquid between the cells.
Water plays a vital role in maintaining all of the body systems and also in repairing any damage to the body. Blood is more than 83 percent water, and in order for it to properly carry out its life-preserving functions, the body must be sufficiently hydrated. The brain, which controls every aspect of the body, is more than 80 percent water. The fluid inside the nerves is also made up of water and minerals.
Water also has a large impact on energy. The liver uses water to metabolize fat into usable energy. Drinking a lot of water speeds up the metabolism and results in increased strength and energy. A drop of 5 percent in body fluids causes a 30 percent drop in energy, and a 15 percent drop in body fluids causes death. Water is also important in keeping the temperature of the body constant.
Because so much of the body is water, it is advisable to drink a large amount of high-quality water to stay healthy. About 2 liters per day is recommended, depending on factors such as the ambient temperature and humidity and a person's level of activity.
7. WHAT IS THE ORIGIN OF THE TERM HONEYMOON
It is commonly thought that the word honeymoon comes from a supposed Babylonian custom of drinking mead, or honey beer.
It is said that the father of the bride would
provide the groom with honey beer for the first lunar month of the
marriage. The drink was said to increase fertility and virility. So honey from the beer and moon from the lunar month made the complete word, and the first month of a marriage became the honeymoon.
It is now thought that the mead-drinking theory is a myth. The first written reference to the word honeymoon was in 1552 by Richard Huloet, well after the days of Babylon. Samuel Johnson also referred to it in the 1600s.
Both Huloet and Johnson define honeymoon as the first month after marriage, when things are sweet like honey. It is thought that moon
relates to the lunar month. Samuel Johnson also proposed another
explanation: Like the moon, the sweetness of the marriage quickly wanes.
8. HOW HARMFUL IS PASSIVE SMOKING?
Passive smoking (also known as secondhand
smoking or environmental tobacco smoking) is a controversial topic and
the subject of many studies. It involves people who don't smoke
inhaling the cigarette smoke of people who do.
Many experts believe that passive smokers are
at risk of developing most of the problems that actual smokers develop.
Studies published in prominent medical journals have found many
detrimental effects of passive smoking. The Journal of the American Medical Association
concluded that up to 40,000 deaths in the United States during the
1980s were caused by passive smoking. Other studies have found that
passive smoking increases the likelihood of heart disease by up to 60
percent. Passive smoking appears to be particularly dangerous for
children, contributing to sudden infant death syndrome and several
respiratory diseases.
A 1997 study published in the British Medical Journal
found a 24 percent greater incidence of lung cancer in nonsmokers who
lived with smokers. In addition, the study found that tobacco-specific
carcinogens were found in the blood of these passive smokers, indicating
the significant risks involved.
The Tobacco Manufacturers Association tries
to discredit the various studies by pointing out that the results of
the studies differ. Some studies have found only a weak connection
between diseases and passive smoking, which the tobacco companies have
seized on as evidence that passive smoking is not harmful.
Most experts, however, now agree that passive
smoking is harmful. In light of the body of evidence, and the fact that
smokers have a choice to smoke but passive smokers don't, many
governments worldwide have banned smoking in the workplace and in quite a
few public areas, including restaurants.
9. WHAT CAUSES PEOPLE TO GO BALD?
Baldness is a condition that plagues many men
and some women (and even other primates). The most common form of
baldness is a progressive thinning of the hair on the head.
Male pattern balding is said to affect around
66 percent of adult men. Also known as androgenetic alopecia, it is
thought to be caused by an enzyme called 5-alpha reductase, which
converts testosterone into dihydrotestosterone (DHT) in genetically
predisposed men. DHT acts by binding to receptor sites on the cells of
the hair follicles to cause specific changes. It inhibits hair growth
because healthy hair follicles start producing thinner and more brittle
shafts of hair and can even die out. Men bald as they age because it
takes time for the susceptible hair follicles to weaken and die.
Baldness in women is thought to occur because of a decrease in estrogen,
a female hormone that usually balances the balding effect of
testosterone.
Many myths are related to baldness, including
these:
1. It is caused by intense intellectual activity. This may have
been believed because the brain is in the head.
2. It is caused by
emotional stress and sexual frustration. Emotional stress can play a
role, but sexual frustration is not considered a reason for baldness.
3.
Bald men are more virile. This may be believed because some forms of
baldness can be prevented by castration.
4. Shaving hair makes it grow
back thicker and stronger. This is untrue, as the number and thickness
of hairs is governed by the follicles underneath the skin.
5. Baldness
is inherited from the mother's side of the family. Genetics plays a
role in balding (and the genes for male balding are on the X
chromosome), but the relevant genes can come from either parent.
Although there is some disagreement as to the
evolutionary basis for baldness, many believe it is due to sexual
selection: Baldness is said to indicate maturity and therefore superior
nurturing abilities. This may have meant that bald men had a higher
status and found it easier to secure partners as they aged.
10. WHAT IS THE BEST WAY TO TREAT SNAKEBITE?
Throughout the years, there have been a
number of recommended first aid methods for treating snakebite. One
reason for the inconsistencies is that different methods are used with
different types of snake. A method that is effective with one type of
snakebite could result in death with another.
However, the following
guidelines are now suggested for most bites:
- The lymphatic system is responsible for the spread of snakebite venom. This spreading can be reduced or delayed by firmly bandaging the bitten area. Point the bandage toward the central parts of the body. This will help to contain the venom in the bitten area. The bandage should not be so tight as to cut off blood flow. It should not be removed until proper medical attention is received and an antivenin administered.
- The limb should be immobilized by applying a sling or splint. The patient should also be immobilized and not allowed to walk or move around. This immobilization will help to prevent the venom from spreading throughout the bloodstream. Coupled with this, the patient should be kept calm to avoid an increase in heart rate.
- The patient should receive nothing to eat or drink.
- The bite area should not be washed or cut open. It is important for traces of the venom to remain so that medical professionals can determine what antivenin to use. It is thought that washing does not remove much venom anyway, nor does sucking the bite using either a pump or the mouth. This should not be done to do so could be dangerous to the caregiver.
- A tourniquet should not be applied. This was the old approach, but it prevents blood flow to the area and stops the natural dissipation of the venom. This can increase its damaging effects. For the same reason, ice should not be applied to the bite.
11. WHAT ARE THE SEVEN WONDERS OF THE NATURAL WORLD?
With the Seven Wonders of the Ancient World
destroyed (with the exception of the Great Pyramid), people began
searching for other wonders. The Seven Wonders of the Natural World is
one of the results. Although there is some disagreement as to what they
should be, there are seven commonly accepted wonders.
- The Grand Canyon is a gigantic gorge of the Colorado River in Arizona. It is about 1 mile deep, up to 18 miles wide, and more than 200 miles long. The multicolored rocks show the geological changes that have occurred with time. The first European to see the canyon was the Spanish explorer Francisco Vasquez de Coronado in 1540.
- Victoria Falls is a waterfall in the Zambezi River in Africa at the border of Zambia and Zimbabwe with a drop of 420 feet. The falls are enormous and produce a thick mist and a loud roar that can be heard up to 25 miles away. British explorer David Livingstone named the falls after Queen Victoria in 1885.
- Mount Everest is a peak in the Himalayan Mountains on the border of Tibet and Nepal. It is the highest peak in the world and was first reached by Sir Edmund Hilary in 1953.
- The Great Barrier Reef is the largest coral reef in the world. It is off the coast of Queensland in Australia and is approximately 1,250 miles long. In some places it is more than 400 feet thick.
- The harbor of Rio de Janeiro in Brazil is breathtaking. Surrounded by low mountain ranges, which extend to the waterside, the harbor is very deep, allowing large boats to enter it.
- The Paricutin Volcano in Mexico is an active volcano more than 8,000 feet high. It formed from a cornfield in 1943 and grew until 1952, spewing so much lava that it buried the village of Paricutin and the town of San Juan Parangaricutiro.
- The northern lights, also called the aurora borealis, are a colorful display of lights that occur at certain times of year in the night sky of the northern hemisphere. They are caused by the interaction of charged solar wind particles with Earth's magnetic field in the upper atmosphere and are most prominent at higher latitudes, near the magnetic poles
