Cell Biology
Today
The study of cell biology has advanced well beyond microscopy. The ability to grow cells allows researchers to perform experiments on cell aging, to learn about the growth of cancerous cells, and about resistance to immunity. Researchers can look further into the cell at the structure and patterns of DNA, first identified by Watson and Crick in 1953. A look at the number of patents issued on these topics gives an idea of the level of activity in this field, as well as its economic value.

Illustration from:
U.S. Patent Number 5,976,790: Comparative Genomic Hybridization (CGH) invented by Daniel Pinkel et al., November 2, 1999.