

Over the last 40 years, biochemistry has become useful at explaining living processes that now almost all areas of the life sciences from botany to medicine are engaged in biochemical research.

The citric acid cycle is typical biochemistry topic because it details with basic chemistry within all living system for metabolism. image: wikipedia










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Commentary, a link between biochemistry and molecular biology

Traditional biochemistry tends to be about the chemistry of living cells. This essentially means using the techniques and principles of chemistry and applying in to what a cell does.  For example it deals with things like concentrations of chemicals within parts of the cell. In particular things like the concentrations of ions like sodium Na+  H+ which lends it self to the concept of pH levels in the cells.  It also deals with chemical reactions within cells. How one molecule ends up as another.  It is less concerned with how these things are facilitated but more about measuring changes of chemicals within the cell. 

It is molecular biology that really starts to investigate the causative mechanisms of the chemistry. For example the changes in pH in a mitochondria are the result of a protein in the membrane called a proton pump.  The biochemist will say there is a pH difference within a mitochondria and there may be some chemicals that enhance/disrupt this process. The molecular biologist will look at the membrane and investigate what is going on there and link it back to what the biochemist has observed.