Science

The speed of light c in relativity is always its value in free space of ~3.00×10^8.

In all material media ,such as air ,water,or glass ,light travels more slowly than this,and atomic particles are able to move faster in such media than does light .

Invention of DNA Fingerprinting

Sir Alec Jeffreys has put thousands of wrong doers behind bars.Almost single-handedly, he’s also set hundreds of innocent people free from prison.Not bad for a guy who spends most of his time in the genetics lab.

Jeffreys invented DNA fingerprinting in 1985.By examining the patterns made by human DNA after it was diced up by restriction enzymes, Jeffreys realized that every person’s DNA produces a slightly different number of various sized fragments.

Jeffreys’s invention has seen a number of refinements since its inception .PCR(polymerase chain reaction ) and the use of STRs (short tandem repeats) have replaced the use of restriction enzymes.

Modern methods of DNA fingerprinting are highly repeatable and extremely accurate, meaning that a DNA fingerprint can be stored much like a fingerprint impression from your fingertip can.More than 100 laboratories in the United States alone now make use of the methods pioneered by Jeffreys.The information generated by these labs is housed in a huge database hosted by the FBI, granting any police department quick access to information that can help match criminals to crimes.

In 1994, Queen Elizabeth II knighted Jeffreys for his contributions to law enforcement and his accomplishments in genetics.

Source : Book

Interesting Facts About Human Body

1. It is estimated that over a lifetime,humans produce a total of 10,000 gallons of saliva. While saliva is necessary for us to taste our food, we cannot taste it before some food dissolves in it.

2.In a single cell, there are six billion “steps” of DNA or body's genetic code. If stretched out,it would measure six feet ,but it is twisted up in a coil in the nucleus of the cell, where its diameter measures only 1/2500 of an inch.

3. Compared to other cells in the body ,brain cells live the longest ,with some living an entire lifetime.

4. The brain is especially reliant on oxygen to function. In fact ,it uses more than 25 percent of the body's oxygen supply.

5. Approximately 90 percent of the body is made up of four elements: oxygen, carbon,nitrogen ,and hydrogen.

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Albert Einstein Theory of Relativity

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If the sun were cold object ,the compression of gravity would make it about the the same size as earth, but 330,000 times more massive.

#Fact

💥What happens when a miniature black hole collides with larger objects ?

If a mini-black hole collides with a larger body,it will simply bore its way through .It will engulf the first bit of matter within which it collides,liberating enough energy in the process to melt and vaporize the matter immediately ahead. It will then pass through the hot vapor ,absorbing it as it goes and adding to the heat,emerging at last as a considerably larger black hole than it was when it entered.

----Isaac Asimov