Promoting a better understanding of lactic acid fermentation

This paper studies Certificate-level (Year 11) students' understanding of anaerobic respiration by analysing their performance on a structured question in a public examination. Many students erroneously stated that carbon dioxide was released during lactic acid fermentation; some even said that oxygen was required for the process. They also held a variety of alternative conceptions about the nature and role of lactic acid fermentation, such as: anaerobic respiration provides more energy for muscular contraction than aerobic respiration; the muscle stops aerobic respiration during vigorous activity; and there is a shortage of oxygen supply during exercise. The barrier to understanding has been attributed to the fact that most textbook accounts of the respiratory processes are incomplete or misleading. A teaching strategy using a series of flow diagrams is suggested to help students to visualize the complex relationship between aerobic and anaerobic respiration.