<prompt> Most impoant extracellular buffer___BicarbonatesPlasma ProteinPhosphatesNitrates  <response>: The most impoant extracellular buffer is bicarbonate. The source of bicarbonate is plasma by filtration. It is non inducible buffer. Proteins: Are the most abundant intracellular buffer. Phosphate: Minor buffer in kidney. The source is plasma by filtration. It is non inducible buffer. Ammonia is a minor buffer, locally produced by tubular cells. Its production increases in metabolic acidosis. It is the only inducible buffer. Principal Buffers in the Body Fluids Extracellular Buffers Intracellular Buffers HCO3 - Major Plasma proteins Phoshate - Minor NH3- minor Organic Phosphate e.g., AMP, ADP, 2,3-diphosphologly DPG Intracellular proteins Hemoglobin Ref: Guyton and Hall 13th edition Pgno: 410-414 