The phrase "reaction center" refers to a specific area or part of a system where chemical reactions happen. It is like the center or focal point where all the action takes place. Full definition
Jennifer Ogilvie, U-M professor of physics and biophysics, studied photosynthetic reaction centers in purple bacteria. (sciencedaily.com)
Over a span of femtoseconds, they followed the light energy through the scaffolding to the cellular reaction centers where energy conversion takes place. (discovermagazine.com)
The solution of the structure of the photosynthetic reaction center from the bacterium Rhodopseudomonas viridis is described, and the structure of this membrane protein complex is correlated with its function as a light - driven electron pump across the photosynthetic membrane. (science.sciencemag.org)