Introduction to Cancer The individual unruly cell that has escaped the normal regulatory control mechanisms is the basic unit of cancer. Inside the nucleus is a substance called DNA, which contains genetic information for the body, organized in units called genes. These genes contain the complete plans for the body. They determine weather you have a blue or a green eye, weather you will have two or four legs, etc. They send out information that tells the cell what chemicals to make, as well as how much and when to make them. In nucleus, genes are joined together, like beads on a chain, into structures called chromosomes. A normal human body cell has 46 chromosomes, which conta