Medical Dictionary. arrhythmia. play. noun arÂ·rhythÂ·mia \Ä-Ërith-mÄ-É\. Medical Definition of arrhythmia. : an alteration in rhythm of the heartbeat either in time or force.
Central metabolism provides mechanisms for the generation of energy from carbon-energy source catabolism and the production of biosynthetic precursors and intermediates for the anabolic pathways essential to maintain cell structure and function.
Substances in the coffee beans do make it into the final drink. In fact, coffee contains several biologically active substances that can affect metabolism: 1  Caffeine â a central nervous system stimulant.  Theobromine and Theophylline â substances related to caffeine that can also have a stimulant effect.