CAIE IGCSE Biology – Respiration quick notes: definition, aerobic vs anaerobic pathways with equations (glucose + O₂ → CO₂ + H₂O; yeast → CO₂ + ethanol; muscles → lactic acid) and lower energy yield in anaerobic.  Includes temperature effects on rate: rises with kinetic energy to an optimum, then falls as enzymes denature—ideal for fast revision.