WHAT ARE HARMONES?

HORMONES -

Hormones have been called the 'chemical messengers' of the body. They are substances that regulate certain bodily functions such as, growth, development, reproduction, and metabolism. There are eight well-defined endocrine (or ductless) glands in the body. The main endocrine glands are the pituitary, thyroid, parathyroids, pancreas, adrenals, testes and ovaries. In all, they secrete at least 25 hormones into the bloodstream. The absence or excess of hormones causes certain bodily malfunctions such as diabetes, goiter, dwarfism, and gigantism. What are these different endocrine glands and what are the hormones they produce?

An endocrine gland is groups of cells., which take away certain raw materials from the blood and convert them into hormones. The hormones are then released directly into the bloodstream. The pituitary gland is situated near the base of the brain. This gland produces a number of hormones, which control most of the functioning of other glands. One of these hormones controls the growth of the body. If it is overactive, it causes an abnormal growth or gigantism. Similarly, if it is underactive it leads to dwarfism.

The thyroid gland secretes a hormone called 'thyroxin', which is rich in iodine. An abnormality in its secretion can cause serious disorders in the body. If the secretion is insufficient in children then they do not grow in a normal way, either physically or mentally. It controls the oxidation of food in the body. If too little thyroxin is produced, people become very fat. This is because their food is changed into fat instead of being oxidized to produce energy. If the diet lacks iodine, the thyroid gland can get enlarged. This is called 'goitre'. Consuming iodized salt may help to prevent goitre. Our body has four parathyroid glands. Each is about the size of a rice grain. Their hormones enable the teeth and bones to make use of calcium. It is also necessary for proper functioning of the nervous system.

The thymus gland is located in the chest region. To begin with, it is large but becomes progressively smaller as the child grows up. The thymus produces thymosin. Although its function is not clearly understood the hormone apparently protects babies from disease. The adrenal glands are located just above the kidneys. These glands produce a hormone called 'adrenaline' in times of a anger, fear or tension. This increases heartbeat and the amount of energy available to the muscles. The pancreas produces two hormones - pancreatic juice and insulin. Pancreatic juice is used in the digestion of food while insulin controls the amount of sugar in the blood. Insufficiency of insulin results in a disease called 'Diabetes Mellitus'. Its excess, however, can cause hypoglycemia, which is characterized by low blood sugar.

Testes and ovaries are male and female sex glands, respectively. Testes produce testosterone, a male sex hormone. The ovaries produce three hormones-estrogen, progesterone (which controls menstrual cycle) and relaxing. Progesterone plays an important role during pregnancy. Relaxin helps widen the birth canal (vagina) just before the birth of a baby. Hormones control the amounts of various chemical constituents in the body; they regulate the rate of chemical reaction inside the body cells during normal and stressful activities and they control the chemical process involved in growth. One of their most important functions is to maintain functions is to maintain the body's internal environment in a steady state. Specific hormones control the balance of water, important minerals such as, sodium, potassium, calcium, and glucose, which is the main source of energy.

Scientists have now developed synthetic methods for producing hormones. These are used to treat hormonal deficiencies. Synthetic sex hormones are used in birth control pills. Cortisone hormone is often used to treat arthritis and allergies.

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WHY DO TEARS COME OUT WHILE WEEPING?

TEARS -

You must have noticed that whenever somebody weeps, tears begin to fall from his eyes. When someone is very happy even then come to his eyes. Do you know why it happens?

When we blink our eyes, many muscles come into play and the eyelids close and open just like stage curtains. The movement of the eyelids is so fast that it does not disturb our vision. The blinking of the eyes is an involuntary action that takes place every six seconds throughout our life. In each eye, there is a 'tear gland' located at the outer corner. There are small tubes or ducts, which carry the tears to the upper eyelids, and from there they fall out of the eyes through other ducts.

Every time we blink our eyes, some fluid comes out through the openings of the tear ducts. This keeps the eyes lubricated and prevents them from drying. When we weep, more fluid comes out through openings of the ducts in the form of tears. It is a reflex action that occurs without our control.
Sometimes tears come out even when we laugh a gra=eat deal. That is because, when we laugh, the muscles squeeze the tear glands, due to which tear begin to flow out.

Tears also come to our eyes when we cut onions because the onion gives off an irritating volatile substance. When it reaches our eyes, tears are produced to protect the eye from irritation. The tears 'wash' the irritating substance away. The same thing happens in the case of smoke. Some sad news also produces tears by reflex action. This happens only when do not have words to express our feelings.

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WHICH IS THE MOST DANGEROUS BIRD IN THE WORLD?

DANGEROUS BIRD -

The cassowary is the most dangerous bird in the world. Its inner toe has a long dagger-like claw that acts as a weapon and can slash open a man's stomach! the cassowary is found in New Guinea and Northern Australia. it is a secretive forest dweller and is seldom seen, but often heard croaking and bellowing. It can't fly but runs at a great speed on its powerful legs. On each foot, it has three toes, the inner one having a long straight claw. It can often be seen giving furious kicks at the trunk of trees without any apparent reason. because of this strange habit, the cassowary is regarded as having a very bad temper. In dense forests, it can grow up to a height of 6 feet and weigh as much as 180 pounds. When it gets annoyed, it jumps in the air and delivers a vicious kick.

It is a bony-headed bird. Its naked blue head is protected by a bony helmet. Its body is covered with coarse hair-like feathers. It is the only member of the family casuariidage. Unlike other birds, the male incubates eggs. At a time 3-6 legs are laid. The eggs are green in color and 13 centimeters long. They are incubated for 50 days in a leafy nest and on the ground. the adult provides parental care to live young ones.

Cassowaries live in family groups or in pairs. they like to be near water, for they swim readily. They are also good fishers. According to zoologists. the cassowary's ancestors were able to fly. But in the process of evolution, it became flightless. It has adapted itself to make the most sufficient use of its environment. Emu, kiwi, weka, and takahe are also flightless birds. Most of the flightless birds are found in Australia and New Zealand.

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WHAT THE DIFFERENT TYPES OF RHINOCEROS?

RHINOCEROS -

The name rhinoceros' has Greek origin. In Greek, rhino means 'nose' and keros mean 'horned'. The animal has one or more curved horns on its long nose. The horns grow throughout its lift. Rhinoceros belongs to the 'odd-toed' group of ungulates. Rhinoceroses are found in Africa and South-East Asia.

The animal carries its large body on the four stouts, short legs. It has three toes on each foot, each toe ending in the separate hoof. Each front foot actually has the fourth toe, too. that is no longer used. The skin of the rhinoceros is very thick and has little hair. They look as if they are wearing heavy armor plating held together with rivets. The horns are composed entirely of hair-like structures at above thickenings of the nasal bones and frontal bones. They are not attached to the skull and may even be torn off infighting. When this happens, they quickly grow again. The horn may be up to 107 centimeters in length.

There are five different kinds of rhinoceroses existing today - two from Africa and there from Asia. The Sumatran rhinoceroses have two horns whereas the other two Asian species - Indian and Javan - have only one. They are all on the verge of extinction but the most endangered is the Javan rhinoceros, which survives only in one small reserve.

The largest of all these is the white rhinoceros from Africa. It stands 1.8 meters (6 feet) high at the shoulder and can weigh over 3 tonnes. An interesting difference between the white and black rhinoceros lies in the shape of their lips. The white rhinoceros has a wider, square-mouth which is very suitable for dropping grass. The black rhinoceros is more of browser and has a pointed upper lip for grazing and plucking leaves and shoots from shrubs and bushes. The other two-horned species, the Sumatran rhinoceros, is the smallest of all, standing only about 4.5 feet at the shoulder and weighing less than a tonne.

Rhinoceros feeds on grass, twigs, and shrubs. It does not hunt other animals for food. During the afternoon heat, it usually buries itself in muddy water. And from here, it emerges with a layer of mud on its skin. This dries and forms a protective coating against insect bites. The huge animal is usually quiet and retiring. But if it is cornered, it can become very fierce and dangerous. A rhinoceros can run at a speed of 30 miles an hour, and use its strong, pointed horns to attack its enemy. In captivity, the rhinoceros may live up to 50 years. A female bears only one young at a time. The calf is born about 18 months after the mating season and remains with the mother for several years.

Now, unfortunately, the rhinoceros is a rare species. Over the centuries, it has been hunted by man for its horns. This is because according to an ancient belief, its horn imparted magical properties to its owner. However, now this second largest land mammal is being protected by law to prevent it from becoming extinct.

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WHY DOES DOG GO MAD?

DOG GO MAD - 

Dogs are regarded as faithful animals and were probably among the first animals to be domesticated by man. But if it goes mad, it becomes very dangerous. A person who is bitten by a mad dog may die if not treated promptly and properly.

A dog goes mad when it suffers from a disease called 'rabies'. This disease is caused by a virus, which is carried in air or by some wild animals and enter's the dog body through a wound or a cut on its skin. The virus is bullet-shaped, having a diameter of about 70 millimicrons and a length of about 210 millimicrons.

When an infected animal bites a dog, the virus contained in the saliva enters the wounds and travels through sensory nerves system. It multiplies there and then begins to destroy the brain cells. The dog becomes lazy, suffers from fever and losses interest in food. In about 4 to 6 weeks, when these viruses affect's the dog brain, the dog growls, barks and saliva forths from its mouth. During this period, the dog can bite anybody. This is the stage when the dog is said to be mad. It is likely to die within 3 to 5 days after these symptoms appear. Some infected dogs do not go mad but show signs of paralysis, a disease called 'dumb rabies'.

When a mad dog bites a man, the virus present in saliva enters the man's body through the wound. Initially, the victim experiences mental weakness and uneasiness, which is followed by fever. He suffers from lack of sleep and feels frightened. The muscles in the throat get slackened and the faces difficulties in swallowing food or liquid. He is afraid of water, being infected by a disease called 'hydrophobia' which means 'fear of water'.

These signs appear in the victim within one to three months after the mad dog's bite. In all cases of dog-bite, the affected portions should be immediately cleaned and anti-rabies injections should be given to the victim within three days of the bite, the number of injections can vary from 3 to 14 depending on the location and number of bites.

The virus of rabies also attacks foxes, jackals, monkeys, bats, cats, and rats. Louis Pasteur introduced the treatment for rabies in 1888. Pasteur Institute of France is a famous center for rabies treatment.

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IS THERE ANY ANIMAL WHICH COMMITS SUICIDE?

SUICIDE -

Lemmings are small, stout, grey or brown animals with short tails and small eyes. These mouse-like rodents live in the colder regions of Northern Hemisphere, such as the mountains of Scandinavia and Lap land. They are between 12 to 16 centimeters ( 5 to 6 inches) in length, with feet covered with fur for protection against cold. They make their nests both above the ground with dry grass and in burrows. They feed on roots, stalks, and moss.

You may have heard stories about lemmings that hundreds of thousands of them march to the sea in a long packed line and jump into the sea. This is only one part of the whole story. The lemmings live high up on the mountainside. In years, when food is plentiful, lemmings breed very quickly to produce enormous population.  This is known as 'population explosion'. The available food is quickly eaten and then large numbers of lemmings migrate in all directions in search of food. As they migrate, many many fall prey to predators while many others fall into the rivers and the seas slipping from the edges of the cliff. They swim for about 15 to 20 minutes and are finally drowned.

No lemming ever returns to the place of its origin. The migration process is repeated every third or fourth year. Scientists have proved that lemmings move away from their houses in large groups because of overpopulation, but they do not drown themselves on purpose.

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WHY DO WE DREAM?

DREAM - 

We spend about one-third of our life in sleep. Sleep is essential for the good health of both mind and body. Sleep is a state of unconscious rest. Even the conscious part of the mind is totally at rest, the subconscious part of the mind continuous working and produces dreams.

About five times during the night, we change from periods of deep sleep to periods of light sleep. And as morning approaches, the periods of light sleep become longer. We dream during the periods of light sleep. In the dream, we make rapid eye movements and some body movements. If we wake up while we are dreaming, we can often remember the dream. No one really knows why we have dreams. But they appear to be an important part of sleep. Scientists have proved that almost everyone dreams three to five times during an 8-hour sleep. Those who claim that they do not dream, in fact, do not remember what they dreamt.

Most dreams are based on events that happened during the day. Others involve fearful sights you might have seen when you were young. In other dreams, wishes you have had for a long time are also fulfilled. Some psychologists contend that during this activity, the brain 'clears its registers' to prepare for the next day's conscious activities. During this period, the pattern of brain waves also changes. It is sometimes recorded for scientific observations. Its recording is called electroencephalogram.

According to some people, their problems have been solved during dreams. Kekule, a great chemist, gave the structure of benzene molecule after having a dream. He was very puzzled about the structure and one night in his dream, he saw a snake biting its tail while in whirling motion. That gave him the idea about the molecular structure of benzene. Some people believe that dreams can foretell the future. So far, scientists have not been able to fully explain this phenomenon.

Some dreams are pleasant, while others called 'nightmares' are related to our suppressed emotions, fears, desires, and needs.

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WHY IS HARD TO WALK UPHILL THAN DOWNHILL?

 UPHILL THAN DOWNHILL -

Generally while climbing up the stairs of a building, a person gets more easily exhausted, than while coming down. To lift heavy articles, greater effort is required. It is harder to walk uphill than downhill. Have you ever wondered why?

We know that our Earth attracts everything towards its center. This is known as the force of gravity of the Earth. It is the force of gravity that holds us on the surface of Earth. When we move away from the Earth's surface, we have to put in extra energy to overcome the force of gravity.

So while going uphill, our muscles have to do more work to lift the weight of our body against the gravity of the Earth. For this, the heart has to pump more blood to the cells. As a result, our lungs have to do more work to pump out the carbon dioxide from the heart, and to replace it with oxygen. Here, for a steep climb, we breathe at a faster pace. If we climb a mountain by two different paths one more steep, and the other less we would feel greater fatigue in the case of the steeper one.

In comparison to the energy required for walking on a horizontal plane, the total value of the extra energy needed for climbing is the weight of the body multiplied by the total height to be climbed. When we walk down a hill, very little energy is required because the body is carried down the slope due to the Earth's gravitational pull. This is why our muscles do less work, and we do not feel tired while walking down a hill.

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WHY DO HOT THINGS BURN US?

THINGS BURN -

An object is said to be hot if its temperature is more than our body temperature. If we touch such an object, heat flows from it to our body and we sense the difference in temperature. In case the object is hotter, it causes pain and may even burn our skin. Similarly, an object is said to be cold if its temperature is lower than our body temperature. When we touch it, heat flows from our body to the object.

We know that our body is made up of molecules., and these molecules are made up of atoms. At normal body temperature, these atoms are in motion or vibrating. The atoms vibrate slowly when cold but faster when hot. When we touch a hot substance with a fingertip, the fast-moving atoms of that hot substance accelerate the motion of the atoms of our fingertip. The molecules at the fingertip suddenly start to vibrate faster, causing pain and a burning sensation. It is the breaking up of the molecules that cause the burning sensation. To repair the damaged cells, blood circulation becomes faster in the affected area, and it is for this reason that the affected part becomes red.

When the temperature of the object touching the body very high, a large number of cells and nerves begin to break up. The hit of the substance dehydrates the cells of the skin and they disintegrate. This is called burning.

Sometimes, very hot substances destroy fats and bones. This causes deeper wounds in the body. The scars caused by such burning are removed by grafting the skin taken from other parts of the body. Burns are classified into four degrees. In first-degree burns, only the superficial layers of the skin become red. In second-degree burns, deeper layers are damaged and blisters are formed. In third- degree burns, all the layers of the skin are destroyed. In fourth-degree burns, not only the skin but also the tissues beneath it are damaged.

Burns are caused not only by heat but also by chemicals, acids, X-rays and radioactive rays.

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WHY DO WOMEN HAVE A SWEET VOICE?

SWEET VOICE -

You may have noticed that the voice of women is generally sweeter than that of men. Even boys have a feminine voice till the age of eleven or twelve years. But later it starts becoming deeper. the voice of girls, however, does not change much with age.

Normally, the age between eleven to thirteen years is known as the puberty age. During this period, some of our glands produce sex hormones. These hormones bring many changes in the bodies of boys and girls. In boys, they are responsible for the growth and appearance of the hair under arms, auxiliary hair, pubic hair and facial hair. The voice of the boys starts becoming deeper. Their bodies produce a hormone called 'testosterone' which is mainly responsible for changing the length and thickness of the vocal cords. This also affects the larynx. As a result, a man's larynx becomes larger than that of a woman. men have vocal cords longer than those in women. Due to this, the frequency or pitch of man's voice becomes lower than woman's and hence the male voice becomes deeper than that of a female.

Though this hormone is not produced in the girls, yet a slight change occurs mainly due to the further growth of their throat, mouth, nose, and upper jaw.

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WHO IS BRIGHTER : GIRLS OR BOYS?

BRIGHTER -

There is a difference of opinion on this question. People have various explanations; some say that girls are brighter than boys while others have the opposite view. Scientists have yet to establish a logical scale by which it can be established that one sex is smarter than the other. Here are some facts, which provide some insight into this question.

The average brain weight of males is slightly more than that of females, and also the average body weight of men is more, therefore, in both sexes, brain weight percentage to the total body weight remains the same. The difference in brain size is not of much significance.

Various tests conducted on groups of girls and boys produced the same results. In tests, dealing with skills, the average score for girls was better. In tests pertaining to technical and mechanical ability, boys fared better. But these figures are not very important because these may not be a good measure of peoples' abilities. besides, this is only an average data on certain tests, one sex may score more than the other but the results are almost same in other tests.

Girls and boys are treated differently right from their childhood. Girls are usually given dolls to play with, while boys get electrical and mechanical toys. Therefore, girls are generally less technical than boys. But now things are changing. Today girls and boys are working together in various technical and non-technical fields, and their capabilities are almost equal. It is, basically, the kind of upbringing and training that decides the ability rather gender considerations. At present we have no scientific evidence by which it can be proved which sex is brighter. Neither sex has a monopoly on any special mental ability. It would be incorrect to judge brightness on gender grounds.

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HOW DID DIFFERENT SUPERSTITIONS BEGIN?

SUPERSTITIONS -

Superstitions have played a unique role in the human life right from the beginning of civilization. Even today, we may find many people who are superstitious about different things. Do you know how different superstitions began?

Ancient man could not explain various natural phenomena like thunder, lightning, and climatic changes. He knew little about the sun, moon, comets, and meteors. So he formulated his own theories about these phenomena, thus leading to the first kind of superstitious beliefs.

A superstition is usually born out of fear, which is contrary to reason and cannot be proved by experience. For instance, a comet was a mysterious phenomenon and was considered unlucky - a sign of imminent plague or war. People also believed that if one looked at the moon for a long time, he would get 'Moonstruck'. In fact, the word 'lunatic' has been derived from the Latin word 'Luna' which means moon. Similarly, farmers used to think that growing moon encouraged the growth of crops.

Superstitions were also built up around animals. In Egypt, cats were worshipped as sacred animals. In Europe, it is thought very lucky to have a black cat walk across one's path. In North America, the reverse is true. In India, a black cat crossing your path is considered as a sign of bad luck. The hooting of an owl is a sign of approaching death, and so on.

Over the centuries, superstitions about 'lucky' and 'unlucky' numbers also developed. For example, 13 is considered to be an unlucky number throughout the world.

Ancient people in Scandinavian countries believed that thunder and lightning were caused when their god 'Thor' threw His hammer at His enemies.

Sneezing is considered a bad omen. When someone sneezes, people often say 'God bless you'. With the advance in science, man has come to understand more about the world around him. But somehow the old beliefs continue to have their hold on people.

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HOW DID THE PRACTICE OF SHAKING HANDS BEGIN?

SHAKING HANDS -

People shake hands more frequently today than they did a few hundred years ago. In ancient times, the hand was considered as a symbol of power and strength. Primitive man used it to kill animals or fight against his enemies. The extended hands were taken to be a gesture of goodwill and friendship by ancient people.

The practice of shaking hands probably originated in ancient Greece. Greeks prayed before their gods with raised hands - a gesture of devotional acts in honor of the deity.

Nowadays, the handshake has become the most accepted form of greetings and occurs in the most varied cultural areas of the world with a few exceptions The Japanese, for instance, normally do not shake hands; they bow and the degree of bending is related to the amount of respect due to the person being greeted. In India, the traditional form of greeting is namaste with folded hands. In the Middle East, people exchange greetings by kissing gently on each other's extended hands.

However, with the passage of time and the influx of Western culture, these forms of greetings are not a rule everywhere although these traditions are still in existence among a large number of people in different regions.

A handshake can reveal one's hidden personality. A firm but smooth grip is considered the best handshake. It sends a message of warmth and friendliness. Handshaking usually accompanies all acts like an introduction, farewell, gratitude and congratulation. It is customary to shake every individual hand when formally joining or departing from groups.

The record number of hands shaken by a public figure at an official function was 8513 by president Theodore Roosevelt of U.S.A. at a New Year's day function on January 1, 1907. However, Scottkillon of Canada holds a handshaking record with over 25000 visitors in just 8 hours at the Exhibition of Expo-92 in Seville.

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HOW DID VARIOUS RELIGIONS ORIGINATE

RELIGIONS -

You must have heard of many religions co-existing in the world today. But have you ever wondered how the major religions originated? It is difficult to say which religion was the first to originate. However, the story of their origin is very interesting. From the beginning of civilization, the man has been worshiping many powers in the hope that they could protect him from different threats in day-to-day life. The man has also been worshipping things which he feared. For this purpose, he selected some powerful or ideal objects for worshipping. A particular spiritual power or ideal was first called a 'sect' and later on 'religion'. Now, the question is: how did the various major religions of the world originate?

Hinduism is not a codified religion and its origin cannot be attributed to any one person or deity. It is basically a way of life coming down from the original Aryan settles in the Indus valley. Buddhism started around 2500 years ago as a result of Gautam Buddha's teachings.

The principal religions in the world today are Hinduism, Buddhism, Confucianism, Taoism, Shinto, Islam, Judaism and Christianity. There are more than 3000 million followers of these major religions. They constitute three-fourths of the world's total population. The approximate number of followers of the different religions is as follows: Christianity 1000 million; Hinduism 520 million; Buddhism 230 million; Confucianism 275 million; Taoism 30 million; Taoism 30 million; Islam 520 million; Judaism 15 million.

The followers of the Chinese philosopher Confucius founded Confucianism. The Tao religion originated from the book Tao Te Ching, written by Lao-tzu in the 6th century B.C. The Shinto religion is the ancient religion of Japan. Similarly, Prophet Mohammed started the Muslim religion (Islam). Likewise, different prophets started in other religions.

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WHY DO PEOPLE GET MARRIED

MARRIAGE -

Marriage is the legally & culturally sanctioned union of a man and women. The basis of marriage varies considerably in different societies.
Why do people get married and how do marriages take place in different customs?

In most marriage ceremonies, customs or contracts involve a set of rights & duties such as care and protection. The couple promise to love and care for each other as long as they live. They formally accept each other as husband and wife and often exchange rings and garlands as symbols of their vows. It is also expected that children born of such union will continue the respective family line.

There are, generally, two types of marriage - civil marriage & arranged marriage. In most countries, people can choose either civil or religious marriage ceremony. In the Indian subcontinent, the ceremony may be held at the house of bride to be solemnized by a priest or holy man. In Western countries as well as in some other parts of the world including India, the ceremony often takes place in Churches, Gurudwaras or Temples.

It is also a tradition in some societies, particularly in Asian regions, for the bride to bring a dowry for her own wealth for groom's family. The ill-effects of such a practice can cause a great deal of tension where mutual understanding does not always work between the families of bride and groom.

In India, marriages are arranged generally by the bride and groom's parents, or through the marriage bureaus and marriage negotiators. With the advent of modern trends, the number of civil marriages is also rising. These trends have provided better legal status for women within marriage. In Western countries, registration of marriage is obligatory.

Weddings are a time of great celebration & festivity. Guests bring gifts for bride & groom and wish them a happy conjugal life. The bride & groom wear beautiful dresses that are specially made or purchased. The bride is also adorned with glittering ornaments.

marriages are made in heaven

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