9.1 Aerobic respirations and the mitochondrion In eukaryotes, the utilization of oxygen as a means of energy extraction takes place in a specialized organelle the mitochondrion Anaerobes: Organisms that. utilize energy-rich compounds through oxygen-independent metabolic pathways such as glycolysis and fermentation Aerobes: organisms dependent on tne presence of oxygen to utilize energy-rich compounds9.1 Aerobic respirations and the mitochondrion In eukaryotes, the utilization of oxygen as a means of energy extraction takes place in a specialized organelle, the mitochondrion. Anaerobes: Organisms that utilize energy-rich compounds through oxygen-independent metabolic pathways such as glycolysis and fermentation. Aerobes: organisms dependent on tne presence of oxygen to utilize energy-rich compounds