Friday 25 October 2013


The combat dance of rattlesnake is one of Nature’s great oddities. Actually, it is not a dance but a curious kind of wrestling combat, and it is believed to be rooted in the instinct of all animals to protect their own territory.
The encounter takes place when two angry snakes, one of them an intruder, meet head-on. The combatants pause for a moment, and then, with a sudden convulsive movement, they simultaneously raise the forward parts of their bodies straight up in the air to a height of about two feet and press against each other.
At the same time, they intertwine their tails firmly together to give themselves a purchase for their upright positions. It looks like an embrace, but it is not. It is a fight, each snake trying to push the other to the ground. Weaving back and forth in the air, the embattled reptiles slam and press the free portions of their bodies against each other with great force. The back of the head offers the most vulnerable target. Each snake knows that a push at this point can easily topple his opponent. To add power to this push, the snake fills their lungs deeply with air to make their bodies more rigid on the attack.
The fight continues for some minutes, during which time the snakes are completely oblivious to any danger that threatens nearby. Finally one snake is brought to the ground. The victor holds him there for a moment and then allows the vanquished snake to escape and glide away unharmed.
Only male snakes engage in this combat dance. And they fight only to drive their opponent from the field, very much as medieval knights used to do. They do not fight to kill. If so, they would use their fangs on each other, since most snakes are susceptible to the fatal effects of their own venom.
The combat dance has not been observed very often. The well-known herpetologist, Ross Allen, says that he has witnessed it only three times in more than more than forty years spent studying the habits of reptiles.


Sunday 20 October 2013



The Sun and its energy
Most of our energy comes from the Sun. The Sun is a big ball of glowing gases, made up mostly of hydrogen. Inside the Sun, hydrogen atoms join together (through a process called nuclear fusion) and become helium. During the fusion process large amount of energy is released. The energy works its way to the Sun’s surface and then radiates out into space in the form of waves. These waves give us heat and light. The energy from the Sun is stored in our food, which provides fuel to our bodies. It happens thus:
  • Plants absorb energy from the Sun (Solar energy) and convert absorbed energy to chemical energy for storage.
  • Animals eat plants and gain the stored chemical energy.
  • People eat plants and meat.
  • Food provides the body with energy to work and play.

The Sun stores its energy in Fossil Fuels
The Sun also provides the energy stored in fossil fuels. Coal, petroleum and natural gas are fossil fuels. They come from the remnants of ancient plants and animals over millions and millions of years. This is how it happened:
  • Hundreds of millions of year ago, before people lied on Earth, trees and other plants absorbed energy from the Sun, just as they do today.
  • Animals ate plants and smaller animals.
  • After the plants and animals died, they slowly became buried deeper and deeper underground.
  • After millions of years, they eventually turned into coal and petroleum.

Although the buried prehistoric plants and animals changed from over time, they still contained stored energy. When we burn fossil fuels today, the stored energy from the Sun is released in the form of heat. The heat is used to warm our homes and other buildings and produce electricity for our lights and appliances.
How does energy get to you?


Energy from Fossil Fuels
Most of our energy comes from fossil fuels. Your home may be heated with oil or natural gas. You may have a kitchen stove that uses natural gas. Cars need gasoline to run. The following shows how energy goes from a primary source to a form of energy that we can use:
  • The fossil fuel is taken to a furnace, where it is burned. The heat produced by the burning fuel is used to heat water that flows through pipes. When the water boils, it becomes steam.
  • The Steam is sent to a turbine. The steam pushes against the blades of the turbine and causes it to spin.
  • A shaft attached to the turbine turns a generator and a spinning magnet produces electricity in coils nearby.
  • The electricity is sent by wires over long distances to homes and businesses. The electricity can then be used for lighting and for running appliances or machinery.


Energy from water
For centuries, people have been getting energy from rushing water. In a hydroelectric plant, water from rivers or dams is used to drive machinery like a turbine. The turbine is connected to a generator, which produces electricity.


Nuclear Energy: In nuclear reactors, Uranium atoms are split into smaller atoms to produce heat. The heat is hen used to produce electricity, just as the heat from burning coal is used.


Saturday 19 October 2013

  



Nursing a sick child often requires more skill and understanding. The mind of a child works differently. He has no experience to guide him. A sick child is naturally afraid, even if you have told him he will be well again in a few days.
Child’s imagination: Every child has a highly active imagination, which becomes even more sensitive when he is sick. You must be careful not to increase his fears. Children have heard adults tell tales about illness and death, including all harrowing details. This sort of exaggeration is harmful to child. Then when he becomes ill, and his imagination is already working overtime, he may be almost scared to death. Therefore, try to keep him calm and quiet. Another instance of the fear in a child is the moment when the doctor prescribes an injection. If so, be sure to set a good example yourself. Don’t cringe when the doctor opens his bag. The child may be watching how you react in this emergency. If you are calm and cheerful, he will try to follow your example.
Fortunately, Nature is kind to young children. Most of their illness last only a few days at most. One minute they seem to be sick and at another they are up and running around as if nothing had happened. Except in certain crippling diseases, they rarely have to stay long in bed.
When your child is sick, be sure to consult the doctor early in the day. Don’t wait till midnight, merely hoping for the best. Remember, the earlier the doctor is consulted, the better for the child and also for yourself. A young child does not have the reserve energies of an adult. He can go downhill very rapidly with certain types of infection. Don’t take a chance, consult the doctor early.
Should you pamper your child? Not necessarily. All children like to be considered as heroes. So don’t pamper your child when he is sick. Sometimes they refuse to take prescribed diet and demand their choice. When this happens, try to explain the child how the planned and prescribed diet helps him become normal soon. Help him to act like a grown-up. At the same time do not make a simple illness seem too important. If your child gets too much attention, he may prefer to remain sick or feign sick.

Don’t allow too many visitors at home when your child is sick. Allow him to see Nature as much as possible. Narrate stories with happy endings. He may want to hear some favourite story over and over again. Either you read for him or narrate. Talk about cheerful things and avoid all morbid discussions. The child recovers fast and brings cheer in you.

The dog family includes wolves, foxes and jackals. The familiar domesticated dogs, which have been bred into a huge number of different shapes and sizes, probably originated from the grey or timber wolf. Unlike cats, dogs tend to hunt in groups, called packs. Their long, powerful legs enable them to run well and for long periods.
The common or grey wolf,  the largest of the dogs and found in forest, tundra and mountains, varies in appearance across its range. It is also called the timber wolf, steppe wolf, tundra wolf and plains wolf.
Wolves eat a wide range of food, from deer to small mammals and even berries and other fruits. Even though they are common in some places, wolves are very rarely a danger to people. There are 35 species of dogs and relatives. The thirty five species, including grey wolf, live in North America, Europe and across Asia.
Red wolf is found in south eastern North America and is exceptionally rare now. Coyotes are common in parts of North and Central America. They are rather like smaller versions of wolves and their strange night howls are the ‘call of the wild’. The maned wolf lives in tall grassland in South America. It has long, graceful legs and attractive red-brown hair. Like pet dogs, wolves put their ears back and bare their teeth when they feel in danger.
Four species of Jackals live in Africa, Southeast Europe and South Asia; Dingo is found in Australia. Dhole or Asian wild dog is found in India, China, and Southeast Asia; African wild dog is mainly found in Southern Africa.
21 species of Foxes are found worldwide except Australia. Red or Common Fox is one of the most adaptable and widespread of all mammals, living in remote country and also scavenging in towns and cities.


Wednesday 9 October 2013




One of the richest sources of protein is the soy bean. This simple food contains a complete protein. It has been cultivated in China and Japan for centuries. Soy beans actually contain twice as much protein, ounce for ounce, as meat and four times as much as eggs. Soy beans also contain a high quality vegetable oil that has no cholesterol in it. Soy oil contains lecithin, which s of value in controlling the level of cholesterol within the body. Soy beans are low in carbohydrates, so that diabetic patients can use them freely. They are highly alkaline, and in addition, contain all the important vitamins.
Sprouted soy beans are used in many parts of Asia. They are an excellent source of vitamin C. They are also rich in vitamins A and B complex. Babies who are allergic to cow’s milk can usually take soy bean milk without any trouble.
In some countries a number of foods are made from the soy bean. These include baked beans, canned or frozen green beans, bean sprouts, soy milk an cheese, vegetable shortening, margarine, and salad oil. They are also used in ice cream and sweetmeats, soy breakfast foods, soy sauce, and soy flour. Different types of soy beans are produced for these purposes.

Modern nutritionists and food chemists are busy in many areas searching for new ways of sing this important protein food. Without doubt soy bean is an excellent answer to the problem of feeding an overpopulated world. It is one of our very best foods, Nature’s gift to man.

Monday 7 October 2013



Antoine Henri Becquerel (1852-1908) was a French Physicist who discovered radioactivity.
Some substances, when they have been exposed to bright sunlight, glow in the dark for some time afterwards. This effect is called Phosphorescence. Henri Becquerel followed in the footsteps of his father and grandfather who had both been well-known physicists. He was interested in crystals which glow (fluoresce) after absorbing sunlight. When Roentgen discovered X-rays in 1895, Becquerel was fascinated. In the meanwhile a Frenchman named Henri poincare, who later became famous as a brilliant mathematician, suggested that phosphorescent substances might give off X-rays. In 1896, a friend and fellow-countryman of Poincare, Antoine Henri Becquerel, decided to put the matter to the test. He exposed crystals of a Uranium compound to sunlight to make them phosphorescent and placed them on thickly wrapped photographic plates. On developing the plates he found that the plates had been blackened by rays from the uranium compounds. It looked as if Poincare had been correct. A few days later Becquerel happened to be developing some old photographic plates to see if they were still good enough to use. The plates had been kept in a drawer in which there were traces of the uranium compounds. He found to his astonishment that those plates had been blackened by the uranium, even though they had been kept in the dark. The blackening had nothing to do with phosphorescence after all. Becquerel had discovered what came to be called radioactivity. He found that the uranium ore pitchblende was more intensely radioactive that even uranium itself. His enthusiasm influenced Pierre and Marie Curie.
The Curies
Becquerel was friendly with Pierre Curie, a lecturer in Physics at the University of Sorbonne in Paris, and his wife Marie, who was a chemist. He mentioned his discovery regarding Pitchblende to them, and they resolved to try to isolate the unknown, powerfully radioactive element that must be present in the ore.
The Curies obtained loads of Pitchblende ‘waste’ from the Austrian government from which the uranium had already been extracted. They worked in an old wood shed in the Sorbonne purifying and separating the ore. In July 1898 they announced that there were not one, but two unknown radioactive elements in pitchblende. They isolated one, which Marie Curie named polonium, after Poland, where she was born. They did not succeed in isolating the second one, which they called radium, until 1902.
For their pioneering work on radioactivity, Becquerel and the Curies were jointly awarded the 1903 Nobel Physics Prize.
The radium the Curies had prepared so far was in the form of a compound. Therefore, they set about producing pure radium. Pierrie, however, was killed in a street accident in 1906, and Marie continued alone. Breaking with all tradition, the Sorbonne offered Pierre’s position to Madame Curie. In 1910 Marie succeeded at last in preparing a minute amount of pure radium. This brought her a second Nobel Prize in 1911. Soon afterwards she helped to found, and became the first director of the Radium institute of Paris.

Marie Curie died of leukemia, a disease of white blood cells. It has since been shown that radiation can cause leukemia, so it is more than likely that Madame Curie died as a result of excessive exposure to the intense radiation from the elements she had discovered. 


Mosquito, a two-winged ‘little fly’ is a menace to humankind. It causes blood loss, transmits diseases like malaria, filaria, dengue, chikungunya, and Japanese encephalitis. There is incredible diversity in the mosquito family. Weighing only about 2.5 milligrams, mosquitoes have survived through the ages. Fossil and zoogeographic evidence suggest that these insects evolved during the dinosaur period of Jurassic Age around 250 million years ago. Though dinosaurs are long gone, these small winged creatures have adapted and evolved to produce extensive taxonomic, genetic and ecological diversity.

Where are they found?
Mosquitoes are found throughout the world except in places that are permanently frozen. They are found amply in the tropics and subtropics. The largest population of individual species occurs in the Arctic Tundra. Out of the 3500 mosquito species, about 350 species have been reported in India.
The diseases they transmit

It is estimated that over 700 million people are affected by the diseases transmitted by mosquitoes. Some of the major diseases are: malaria, filaria, dengue, chikugunya, Japanese Encephalitis (JE), yellow fever, Western Nile Fever (WNF), Western Equine Encephalitis (WEE), Eastern Equine Encephalitis (EEE), Venezuelan Equine Encephalitis (VEE), and California Encephalitis (CE).
Varieties of Mosquitoes Anopheles

Anophelinae comprises 450 species. Sixty-six of these are medically crucial for their plasmodium-carrying capacity. In our country, 58 Anopheline species have been recorded of which 10 are known to be malarial vectors.

How to identify Anopheles
Anopheles can be identified by the three to four black spots on the upper edge of the wing. It has grayish brown body and pale bands on maxillary pulp. Male mosquitoes have antennae that look like brush. In females, antennae do not have such dense hairs. The Primary vector An Culicifacies has widespread distribution and can efficiently transmit both ordinary and cerebral malaria. It breeds proficiently during monsoon and causes incidence of malaria intensify.

The other varieties are: An. Stehensi, an urban vector; An.fluviatilis that inhabits hilly regions; An.minimus found in tea garden belts and foothill regions; An.dirus, mainly confined to the forest and forest fringe areas; An.minimus, dirus and fluviatilis maintain stable malaria in the northeastern states. An.Sundaicus is at present restricted to Andaman Nicober islands, though it was earlier prevalent in Odisha. Besides malaria transmission An.gambiae, An. Funestus etc. carry the filarial parasite in some parts of the world including East Africa, Papua New Guinea. An.barbirostris and An.hycranus can transmit Japanese encephalitis virus also.
Why they feed on: Major Anopheline vectors are anthropophilic and feed on the blood of humans inside the house. The biting hours vary through night (depending on the species) with a flight range of two to three kilometers. Their flight sound is not audible.

Where they breed: Anopheles breed in fresh water bodies like riverside, lakes, cisterns, wells, paddy fields etc. But few species can breed even in foul water, muddy ponds and marshlands.