| OCR Text |
Show Units of Heredity Keep Bodies Alive, Revealed at Genetics Society Meeting Genes, the invisible units of heredity, her-edity, do double duty. They determine deter-mine the expression of the body's thousands of characters, such as color col-or of hair or eyes, and they also serve a general purpose in merely keeping you alive. If every gene needed for every special purpose were not also present in every cell, even where it is not needed, you just wouldn't be alive at all. This double function of genes was brought out by Dr. M. Demerec of the Carnegie Institution of Washington, Washing-ton, at the meeting of the Genetics Society of America recently. Every cell in the body contains exactly the same set of genes as every other set. The cells in your toes have the same hair-color gene a the cells on the top of your head. But just because you have no hair on your toes is no indication that those particular genes are lacking there. If they were not present the cells themselves would not exist. There would not be any toes. There would not even be any you. And so for all the rest of the genes. The discussion was conducted in an endeavor to find out more about the working of genes how they operate op-erate to make our hair blond or brunette, our eyes blue or brown, our legs long or short, our dispositions disposi-tions placid or vehement. Genetics thus met embryology. Genes act like enzymes, which are chemical agents that change things without themselves being changed. The digestive ferment pepsin pep-sin is an example of an enzyme. But genes are not enzymes, chemically chem-ically speaking. They are much more complex in their makeup and they decrease and multiply themselves them-selves which ordinary enzymes are unable to do. |
