LIFE 102 Lecture Notes - Lecture 11: Facultative Anaerobic Organism, Anaerobic Respiration, Acetyl-Coa
Document Summary
In alcohol fermentation, pyruvate is converted to ethanol in two steps. Obligate anaerobes carry out fermentation or anaerobic respiration and cannot survive in the presence of o2. Yeast and many bacteria are facultative anaerobes, meaning that they can survive using either fermentation or cellular respiration. In a facultative anaerobe, pyruvate is a fork in the metabolic road that leads to two alternative catabolic roads. Catabolic pathways funnel electrons from many kinds of organic molecules into cellular respiration. Glycolysis accept a wide range of carbohydrates. Proteins must be digested to amino acids; amino groups can feed glycolysis or the citric acid cycle. Fats are digested to glycerol and fatty acids. Fatty acids are broken by beta oxidation and yield acetyl coa. An oxidized gram of fat produces more than twice as much atp as an oxidized gram of carbohydrate. Regulation of cellular respiration via feedback mechanisms. Feedback inhibition is the most common mechanism for metabolic control.
