Genes are the primary units of inheritance in all organisms. A gene is a unit of heredity and corresponds to a region of DNA that influences the form or function of an organism in specific ways. All organisms, from bacteria to animals, share the same basic machinery that copies and translates DNA into proteins . Cells transcribe a DNA gene into an RNA version of the gene, and a ribosome then translates the RNA into a sequence of amino acids known as a protein. The translation code from RNA codon to amino acid is the same for most organisms. For example, a sequence of DNA that codes for insulin in humans also codes for insulin when inserted into other organisms, such as plants. 
Those taking college courses in the sciences likely already have a great number of resources at their disposal courtesy of their school library. But what about those late night study sessions when you need information — and need it fast — and don’t have time for a trip to the library? Or when you just want to learn new information without having to leave the house? That’s when these 100 reference sites will come in handy, letting you look up everything from the basics of the periodic table to the intricacies of human DNA.