With more than one hundred billion neurons, one thousand billion glia, and numerous different types and connections in between, the sheer number and variety of cells in the human brain explain why it is often described as the most complex structure in the universe.
Moreover vast armies of molecules are needed to build each cell and enable it to perform the tasks of a fully operational nervous system.
To understand the brain therefore requires an understanding of its constituent cells and molecules. This allows us to ask how molecules interact within each cell, how cells work together to create as something as complex as the brain - and how to compensate when its complexity is disrupted by injury or disease.
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Techniques routinely in use include protein chemistry (SDS-PAGE, FPLC), immunocytochemistry (western blotting, immunoprecipitation), live/fixed cell confocal imaging, genetic manipulation and molecular cloning, cell transfection, electrophysiological recording.