A professional who studies physical principles of living cells and organisms, their electrical and mechanical energy, and related phenomena. Responsibilities include:

• Conducts research to investigate dynamics in such areas as seeing and hearing; the transmission of electrical impulses along nerves and muscles, and damage to cells and tissues caused by x rays and nuclear particles; manner in which characteristics of plants and animals are carried forward through successive generations; and absorption of light by chlorophyll in photosynthesis or by pigments of eye involved in vision.
• Analyzes functions of electronic and human brains, such as transfer of information into brain from outside, transfer and manipulation of information within brain (thinking), and storage of information (memory).
• Studies spatial configuration of submicroscopic molecules, such as proteins, using x ray and electron microscope.
• May specialize in one activity, such as use of radiation and nuclear particles for treating cancer or use of atomic isotopes to discover transformation of substances in cells.