Molecular Biology

'Molecular biology' is the branch of biology that studies biological activity at the molecular level — particularly the interactions between DNA, RNA, and proteins that constitute the machinery of heredity and metabolism. It emerged in the mid-twentieth century as the confluence of genetics and biochemistry, promising that the secrets of life could be read from the molecular alphabet. That promise was half-kept: molecular biology delivered extraordinary mechanism but failed to deliver the organizational principles that turn mechanisms into living systems. The central dogma — DNA makes RNA makes protein — describes information flow, not system function. To understand why cells do what they do, molecular biology must be integrated with systems biology, with the physics of protein folding, and with the evolutionary logic of comparative genomics.'