American student, David - not his real name - explains why he chooses to buy illegal drugs on the so-called 'dark web'. You don't have to go in front of a street dealer, where there might be a risk of violence, he adds. And it is not just drugs which are available on this online black market. Fake passports, guns - even child pornography.
Genetic material is that substance which not only controls the inheritance of traits from one generation to the next but is also able to express its effect through the formation and functioning of the traits. Components of genetic material which control characters are called genes. Genes are located over chromosomes. In sexually reproducing organisms, an indiÂ­vidual receives one genome or one set of chromosomes (and hence genes) from male parent and a second genome or set of chromosomes from female parent.
DNA, or deoxyribonucleic acid, is the hereditary genetic material for most living organisms. DNA is present in cells in the form of a double-stranded helix that is composed of long strands of nucleotides. The unique sequence of nucleotides within the DNA molecule stores the genetic information. process by which an organism is genetically changed, resulting in a mutation, which is a change in the DNA sequence of a gene. It may occur naturally, for example, due to natural exposure to ultraviolet (UV) light or chemicals; or it can happen deliberately for the purpose of increasing genetic variation of a species.