Careers in Biophysics
The first career in biophysics began when Conrad Roentgen discovered that X-rays could be used to treat cancer and it became necessary to measure how much energy human tissue absorbs when exposed to various kinds of radiation. There are now many medical physicists who help physicians at hospitals diagnose and treat various diseases. In addition to human beings, biophysics jobs incorporate the study of all levels of biological organization, from molecules to ecosystems. Careers in molecular biophysics approach questions in biochemistry and molecular biology quantitatively by using fluorescent imaging, electron microscopy, X-ray crystallography, and spectroscopy based on nuclear magnetic resonance and quantum tunneling. Molecular biology, of course, is concerned with important molecules like enzymes, DNA, and proteins. The structure of DNA was determined by X-ray crystallography. Molecular biophysics jobs often overlap with nanotechnology, which involves manipulating materials one atom or one molecule at a time.
Biophysics careers also overlap with systems biology and bioengineering. Bioengineering applies engineering principles to biology and medicine, an example being designing prosthetics. Systems biology is the study of organ systems (biology systems) with an integrationist rather than a reductionist approach. The scientific method usually is associated with identifying the components of interactions and showing how complex systems can be reduced to simple systems. However, in biophysics work an attempt is made to understand the complexity of biological systems by observing multiple components simultaneously and integrating the observations with mathematical models and an understanding of statistical mechanics, thermodynamics, and chemical kinetics.
Career biophysicists discovered the self-generating wave of electrochemical activity that allows nerve cells to propagate information over distances (action potential). The nerve cells of squids were used because the nerve axons are 1000 times wider than in humans, making it easier to insert electrodes. It was discovered that the action potential was caused by changes in the permeability of the cell membrane to sodium and potassium.