BI110 Lecture Notes - Cellular Respiration, Phosphofructokinase, Glycolysis
Document Summary
Allosteric control of glycolytic enzyme phosphofructokinase: high atp inhibit, high citrate (from citric acid cycle) inhibit, high amp (i. e. low atp) activate. Coa funnels products of many oxidative pathways into citric acid cycle. Many reactions are reversible: intermediates of glycolysis and citric acid cycle also diverted & used as substrates for anabolic pathways (p. 130-131) Fatty acid part of fats has more energy per unit of weight than glucose. Aerobic respiration because oxygen is the ultimate electron acceptor. We need oxygen in order to make atp. Reality is that some organisms and some tissues (specific cell types) can make atp even in the absence of oxygen. Atp can be made in absence of oxygen: fermentation. Once pyruvate made in glycolysis, if oxygen is not present, the pyruvate never enters the citric acid cycle, it will stay in cytoplasm so fermentation is the process that is used. Although they lack mitochondria, prokaryotes have respiratory electron transport chains, located on internal membranes.
