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.
Some of the most toxic waste substances produced by metabolism are small nitrogen-containing compounds called nitrogenous wastes. About 50 % of nitrogenous waste is urea, a by-product that is produced when protein is broken down by the body.Protein is broken down into amino acid and some of it forms ammonia, which is very toxic. The liver, however, quickly converts it to urea, which is a less harmful waste.bout 50 % of nitrogenous waste is urea, a by-product that is produced when protein is broken down by the body. Protein is broken down into amino acid and some of it forms ammonia, which is very toxic. The liver, however, quickly converts it to urea, which is a less harmful waste.