What is the disadvantage of glycolysis?
The correct answer and explanation is :
Disadvantage of Glycolysis
One major disadvantage of glycolysis is that it is inefficient in energy production compared to aerobic respiration. Glycolysis produces only 2 ATP molecules per glucose molecule, whereas aerobic respiration can generate up to 38 ATP molecules per glucose.
Explanation (300 words)
Glycolysis is the first step of cellular respiration, occurring in the cytoplasm of cells. It breaks down one molecule of glucose (C₆H₁₂O₆) into two molecules of pyruvate, generating 2 ATP and 2 NADH molecules in the process. While glycolysis is beneficial because it can function in both aerobic and anaerobic conditions, it has several disadvantages.
The primary drawback of glycolysis is its low energy yield. The process produces only 2 ATP per glucose, which is significantly lower than the ATP output of aerobic respiration (which can generate up to 38 ATP per glucose). This means that cells relying solely on glycolysis for energy need to consume large amounts of glucose to meet their energy demands.
Additionally, glycolysis leads to the accumulation of pyruvate and NADH, which must be further processed. Under anaerobic conditions, pyruvate is converted into lactic acid (in animals) or ethanol and CO₂ (in yeast) through fermentation. This leads to lactic acid buildup, causing muscle fatigue and cramps. In contrast, in aerobic respiration, pyruvate enters the mitochondria, where it is efficiently broken down to produce more ATP.
Another disadvantage is that glycolysis produces NADH, which needs to be recycled back to NAD⁺ to sustain glycolysis. If NAD⁺ is not regenerated, glycolysis halts, stopping ATP production and leading to cellular energy crisis.
In conclusion, while glycolysis is a quick and universal energy-producing pathway, its low efficiency, dependence on glucose, and potential for harmful byproducts make it less ideal than aerobic respiration for sustained energy production.