News. The invention of the Polymerase Chain Reaction (PCR) radically changed biology. The technique was considered so important that the Nobel Prize was awarded to its inventor, Kary Mullis, in 1993.Thanks to this technique, very small samples of DNA (from as little as a single cell) can be analyzed.ews. The invention of the Polymerase Chain Reaction (PCR) radically changed biology. The technique was considered so important that the Nobel Prize was awarded to its inventor, Kary Mullis, in 1993.
The smallest prime number, according to primality as defined by modern mathematicians, is 2. To be prime, a number must be divisible only by itself and 1. All other numbers are known as composites.
A prime number is a number whose only proper divisor is 1. Thus a prime number can be composed only of 1's. 17 and 29 are prime numbers. Again, 1 is a proper divisor of every number (except itself), but a prime number has 1 as its only proper divisor.