GENERAL KNOWLEDGE Pt.- I

• WHO IS A LEXICOGRAPHER?

THE author or compiler of a dictionary is called lexicographer.

• WHAT IS THE DIFFERENCE BETWEEN KNOWLEDGE AND WISDOM?

Most people think that wisdom and knowledge are the same thing but actually they are two different sides of the same coin. Knowledge is nothing but the facts known by a person whereas wisdom is the combination of experience and knowledge, with the power of applying them or soundness of judgement in a person.

• WHAT IS GENOME MAPPING?

A genome is the entire DNA in an organism, including its genes. In human beings the number of genes is between 30,000 to 40,000. Genes are instructions that give organisms their characteristics. The instructions are stored in each cell in the Deox ribonucleic Acid (DNA). DNA is made up of four similar chemicals called bases, which are repeated many times through out a genome. It is estimated that the human genome has more than 3.2 billion pairs of bases. DNA molecules are subdivided into chromosomes and each organism has a characteristic number of chromosomes. For humans, the number is 46 (23 pairs) and this complete set of genetic information is called the genome. Mapping is the process of identifying discrete DNA segments of known position on a chromosome, which are then used for sequencing.

• WHY DO OUR FINGERNAILS GROW FASTER THAN OUR TOENAILS?

Fingernails grow two to three times faster than toenails. A fingernail replaces itself in about six months while a toenail takes a year. Feet are farthest a field in the circulatory scheme of things. A better blood supply to the fingers keeps them chugging along at a faster clip. Nails are basically protective and since our fingers are busier than our toes, they are more likely to need replacing. Also, constant exposure to sun and air may aid their growth. Feet are locked up in shoes most of the time.

• TO WHICH FAMILY DOES THE PORCUPINE BELONG?

Porcupines are large rodents whose bodies are covered with a characteristic coat of sharp spines or quills. Porcupines are divided into two groups, old world porcupines and new world porcupines, Old world porcupines tend be larger than the new world porcupines, live on the ground and the quills on their body are distributed in clusters.

They belong to the family Hystricidae. New world porcupines are smaller and tend to live in trees. Their quills grow separately rather than in clusters. They belong to the family Erethizontidae.

• WHAT IS THE DIFFERENCE BETWEEN A SEAL AND A SEA LION?

The scientific name for this group of animals is Pinnipedia, Latin for 'fin-footed', and refers to the modification of limbs to flippers. Pinnipeds are mammals with four flippers — one pair in front and one at the back. They are warm-blooded, nurse their young, breathe air and have hair. The sea lion has small, tiny external ear flaps. Seals have no flaps. The front flippers of sea lions are long, have no hair and nails. Seals' front flippers are short, blunt, covered with hair with nails on the ends. Sea lions can turn their hind flippers forward to move on land but seals cannot do so.

• WHAT ARE NUTRACEUTICALS?

Nutraceuticals are foods, or parts of foods, which provide medical or health benefits, including prevention and treatment of disease i.e. nutrients with medical implications. Nutraceuticals, which are generally made from herbal/ botanical raw materials. are functional foods or food omnocnronic disease, aoove ana oeyond their basic nutritional functions. A functional food is similar to conventional food, while a nutraceutical is isolated from a food and sold in dosage form, in both cases the active components occur naturally in food.

• WHY DO RAIN-BEARING CLOUDS LOOK BLACK?

The colour of any object depends on its ability to reflect selected wavelengths of light. Consequently, if the object does not reflect any colour, it appears black. The tiny droplets of water in rain clouds scatter the white light of the sun. Red is scattered first, and violet the last. This happens at such a high altitude that no rays of the sun reach the bottom of the cloud. Thus, we do not see the rays of the sun, and this results in a dark effect. As normal clouds have no water, the light is not scattered and thus look white.

• DO ALIENS REALLY EXIST?

IT is certainly known that at least in our solar system, in the planets revolving around the sun and, in the satellites of these planets, there are no life forms that can pose a threat to mankind.

• WHAT IS SPECIAL ABOUT POLAR BEARS?

The polar bear is the world's largest bear. During summer, they eat rodents and berries available on the plants there. They are superb swimmers and have been seen in water hundreds of miles from land. Their thick and dense fur keeps their skin dry, and their furry paws give them a non-slip grip on ice. It goes up to the water surface, takes a deep breath, and goes back down again. When the oxygen body finishes, they absorb some oxygen dissolved in the water, which they can keep for only a few minutes, after which they have to go to the surface again. Its scientific name is Thalarctos maritime and found in the Arctic region.

• WHAT IS THE PROCEDURE TO DIFFERENTIATE BETWEEN BLOOD GROUPS?

The blood group is found out by adding two chemicals Anti Sera A and Anti Sera B to the sample. If the sample gets agglutinated by Anti Sera A, and not by Anti Sera B, the sample is A. If it gets agglutinated by B, but not by A, the sample is B. If it gets agglutinated by both, the sample is AB, and if by neither, the sample is 0. The Rh factor is found out by adding another chemical, Anti Sera D to the sample. If the sample gets agglutinated, it has a positive Rh factor, else it has a negative Rh factor.

• WHAT IS HANSEN'S DISEASE?

Hansen's disease, commonly known as leprosy, is named after the Norwegian Dr Armadeus Hansen who established the cause of leprosy as Mycobacterium leprae. Leprosy is one of the oldest diseases known to mankind and although it is much less frequent today, it still remains a problem in the developing world. Contrary to popular belief, leprosy is not very contagious and is spread mainly by nasal droplets in early stages. Only prolonged skin-to-skin contact will cause the disease. It is completely treatable but treatment is prolonged and cure is slow.

• WHAT IS LEPTOSPIROSIS?

Leptospirosis, popularly known as Well's disease, is caused by a spirochaete (a special type of bacteria) which usually invades the human body through cuts and abrasions, especially following prolonged immersion in water. Manifestations include generalised weakness, high fever, muscle pain, conjunctivitis, vomiting, diarrhoea, jaundice. Treatment revolves around general care, antibiotic therapy and attention to life-threatening complications like kidney failure, profuse bleeding, etc.