What characterizes anaerobic metabolism?

Anaerobic metabolism is characterized by the conversion of glucose into energy in the absence of oxygen. In this process, glucose undergoes glycolysis, resulting in the production of pyruvate. When oxygen is scarce or absent, pyruvate is then converted into lactic acid. This type of metabolism is particularly important during intense physical activity when the demand for energy exceeds the oxygen supply, leading to a rapid production of energy, albeit less efficiently compared to aerobic metabolism.

The importance of this process lies in its ability to provide immediate energy under conditions where oxygen is not available, which is essential for survival during short bursts of exertion. Additionally, while anaerobic metabolism generates energy quickly, it is not sustainable for long periods due to the accumulation of lactic acid, which can lead to muscle fatigue.

The other options describe different metabolic processes that involve oxygen or different pathways for energy production. For instance, the first option refers to aerobic metabolism, where oxygen is used to completely oxidize glucose. The third option relates to the complete breakdown of fatty acids, typically an aerobic process as well. The fourth option discusses gluconeogenesis, which is the synthesis of glucose from non-carbohydrate sources and occurs mainly in the liver, also requiring energy input rather than functioning