Learning Objectives for this Section Aerobic respiration (def)
is the aerobic catabolism of nutrients to carbon dioxide, water,
and energy, and involves an electron transport system (def) in
which molecular oxygen is the final electron acceptor. Most
eukaryotes and prokaryotes use aerobic respiration to obtain
energy from glucose. The overall reaction is: C6H12O6 + 6O2
yields 6CO2 + 6H2O + energy (as ATP) This type of ATP production
is seen in aerobes and facultative anaerobes. Aerobes are
organisms that require molecular oxygen because they produce ATP
only by aerobic respiration. Facultative anaerobes, on the other
hand are capable of aerobic respiration but can switch to
fermentation, an anaerobic ATP-producing process, if oxygen is
unavailable. Aerobic respiration involves four stages:
glycolysis, a transition reaction that forms acetyl coenzyme A,
the citric acid (Krebs) cycle, and an electron transport chain
and chemiosmosis. We will now look at each of these stages. ©
Gary E. Kaiser All Rights Reserved