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Why are viruses at the borderline of living and non-living things?

A virus has a very simple composition. It has a protein sheath inside which there is a strand of DNA. A virus shows some properties akin to living organisms. However, unlike other organisms, they show some properties that are akin to non-living things. They can undergo crystallization and in that form, survive for billions of years. They can survive very …

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Why are there waves on the sea?

Only very rarely are the seas completely still. These were the times that sailors on the old sailing ships feared the most – even more than they feared the worst storms. They became becalmed, which meant that no wind was blowing to fill the great sails to carry them to their next port of call. The sea would be motionless …

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Why are stars grouped in constellations?

People who gazed at the skies in ancient times believed that they could see the shapes of animals and peoples traced out in the stars. These star groups, or constellations, have the Latin names of the shapes, and astronomers use the names in identifying stars. But the stars in a constellation do not belong to any actual group in space …

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Why are Some Plants Non-vegetarian?

Are you scared of going to the forest because you think there are man-eating tigers in the forest? What would you do if there were man-eating plants too? Don’t worry. Man-eating plants do not exist. But insect and animal-eating plants do. They are what you would call non-vegetarian plants. In fact, there are 500 varieties of plant species that trap …

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Why are some people diabetic?

Diabetics are people who suffer from diabetes. The main kind of diabetes affects the pancreas, which is gland that produces a hormone called insulin. This hormone controls the amount of sugar in the blood, which provides the energy for the body. In diabetes, insufficient insulin is produced and the sugar level is uncontrolled, resulting in illness. Diabetes usually cannot be …

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Why are some metals chromium plated?

Some metals are chromium plated to make them look more attractive and to prevent them from corroding or rusting. Chromium is a silver white, hard, brittle metal which was discovered in 1798 by N.L. Vauquelin. Its non-corrosive, high strength, heat resistant characteristics are utilized in alloys and as an electroplated coating. In electroplating, the article to be plated is connected …

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Why are some materials colder to the touch than others?

Provided it has not been heated, a metal object normally feels quite cold. Something made of wood feels less chilly and cloth doesn’t feel cold at all. Yet all these objects have the same temperature! The reasons is that your fingertips are warmer than the objects. Heat therefore flows into the metal from your fingertips, sharply lowering their temperature, so …

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Why are planets generally spherical?

The gravitational pull of each planet basically tries to pull everything within its field toward the planet’s centre, including the planet’s own mass. As all areas of a planet are being pulled equally toward the centre, the planet takes a spherical shape, with all points on the surface being more or less equally distant from the centre.

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Why are only a few metals magnetic?

Only the metals iron, nickel, cobalt and some of their alloys can be made into strong magnets. However, an electric current also gives a strong magnetic field when if flows through a coil. The Earth has magnetic field too, probably because of electric currents circulation in its core. There is a connection here. The atoms of which all substances are …

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