Humber Admissions Practice Test

What type of metabolism produces lactate from glucose?

1. Aerobic metabolism

2. Anaerobic metabolism

3. Oxidative phosphorylation

4. Cellular respiration

The correct answer is: Anaerobic metabolism

The production of lactate from glucose occurs during anaerobic metabolism. This process happens when there is a deficiency of oxygen, leading the body to rely on glycolysis, which breaks down glucose to generate energy. In the absence of sufficient oxygen, the end product of glycolysis is converted into lactate instead of being fully oxidized to carbon dioxide and water through aerobic pathways. Anaerobic metabolism is especially prevalent during high-intensity exercise when oxygen levels are insufficient to meet the energy demands of the muscles. The accumulation of lactate contributes to the feeling of muscle fatigue, but it also allows for a quick production of energy when the body is in an oxygen-limited state. In contrast, aerobic metabolism uses oxygen to fully oxidize glucose, leading to the production of carbon dioxide, water, and a high yield of ATP (energy). Oxidative phosphorylation is a specific step within aerobic metabolism and cannot occur without oxygen, making it distinct from anaerobic processes. Cellular respiration encompasses both aerobic and anaerobic pathways, but it is more specific in this scenario to identify the anaerobic process as the one that produces lactate from glucose. Therefore, anaerobic metabolism is the most precise answer to the question at hand.