Think of The FITT principle as a set of rules that must be adhered to in order to benefit from any form of fitness training program.These rules relate to the Frequency, Intensity, Type and Time (FITT) of exercise...gain, intensity has a say and particularly grueling strength sessions may last as little as 20 - 30 minutes. Perhaps the most important principle of training (that ironically doesn't have it's own letter in the FITT principle) is rest.
Scientists knew the DNA could be uncoiled from the nucleosome, but it was assumed that the two ends were symmetric, meaning uncoiling the DNA would be like untying a shoe. University of Illinois researchers found that the DNA is actually very asymmetric, like the string wrapped around a yoyo.
Sequencing DNA means determining the order of the four chemical building blocks - called bases - that make up the DNA molecule. The sequence tells scientists the kind of genetic information that is carried in a particular DNA segment. For example, scientists can use sequence information to determine which stretches of DNA contain genes and which stretches carry regulatory instructions, turning genes on or off. In addition, and importantly, sequence data can highlight changes in a gene that may cause disease. In the DNA double helix, the four chemical bases always bond with the same partner to form base pairs. Adenine (A) always pairs with thymine (T); cytosine (C) always pairs with guanine (G). This pairing is the basis for the mechanism by which DNA molecules are copied when cells divide, and the pairing also underlies the methods by which most DNA sequencing experiments are done.