Definition of anaerobic

The word "anaerobic" originates from the Greek words "an" meaning "without" and "aer" meaning "air" or "oxygen". In biology, anaerobic refers to the absence of oxygen or the inability to use oxygen in a process. The term was coined in the mid-19th century by German biologist Friedrich Miescher, who studied the effects of oxygen on yeast fermentation. He noticed that yeast could ferment sugars in the absence of oxygen, producing lactic acid or ethanol as byproducts. This discovery led to the development of the concept of anaerobic metabolism, which is the process by which organisms generate energy without using oxygen. Today, anaerobic refers to a wide range of biological processes, including fermentation, respiration, and metabolism, that occur in the absence of oxygen or in environments where oxygen is limited.