The New Genetics Chapter 1: How Genes Work People have known for
many years that living things inherit traits from their parents.
That common-sense observation led to agriculture, the purposeful
breeding and cultivation of animals and plants for desirable
characteristics. Firming up the details took quite some time,
though. Researchers did not understand exactly how traits were
passed to the next generation until the middle of the 20th
century. Now it is clear that genes are what carry our traits
through generations and that genes are made of deoxyribonucleic
acid (DNA). But genes themselves don't do the actual work.
Rather, they serve as instruction books for making functional
molecules such as ribonucleic acid (RNA) and proteins, which
perform the chemical reactions in our bodies. Proteins do many
other things, too. They provide the body's main building
materials, forming the cell's architecture and structural
components. But one thing proteins can't do is make copies of
themselves. When a cell needs more p