B12 Respiration

• Cellular respiration


  An exothermic reaction that occurs continuously in the mitochondria of living cells to supply the cells with energy
• Aerobic respiration


  Glucose + Oxygen → Carbon dioxide + Water
• Anaerobic respiration in muscles


  Glucose → Lactic acid
• Anaerobic respiration in plant and yeast cells


  Glucose → Ethanol + Carbon dioxide
• Anaerobic respiration in yeast cells is called fermentation
• Metabolism


  The sum of all the reactions in a cell or the body
• Metabolic processes


  • Synthesis and breakdown of carbohydrates, proteins, and lipids
• During exercise


  Heart rate, breathing rate, and breath volume increase to supply muscles with more oxygenated blood
• If insufficient oxygen is supplied during exercise


  Anaerobic respiration takes place, leading to the build-up of lactic acid
• During long periods of vigorous exercise


  Muscles become fatigued and stop contracting efficiently
• Oxygen debt


  The amount of oxygen needed to react with the lactic acid to remove it from cells after exercise
• Removal of lactic acid


  Lactic acid in muscles is transported to the liver in the blood, where it is converted back to glucose