Which of the following statements is FALSE?
glycolysis can occur with or without oxygen
glycolysis occurs in the mitochondria
glycolysis is the first step in both aerobic and anaerobic respiration
glycolysis produces 2 ATP, 2 NADH, and 2 pyruvate
The false statement is: "glycolysis occurs in the mitochondria".
The statement "glycolysis occurs in the mitochondria" is FALSE.
To determine which of the statements is FALSE, let's go through each statement and its corresponding explanation.
Statement 1: Glycolysis can occur with or without oxygen.
Explanation: Glycolysis is a metabolic pathway that breaks down glucose into pyruvate. It is the initial step of cellular respiration and can occur both with or without oxygen. When oxygen is present, the pyruvate produced in glycolysis can enter the mitochondria for further breakdown in aerobic respiration. However, in anaerobic conditions where oxygen is not available, pyruvate can undergo fermentation to produce other byproducts like lactate.
Statement 2: Glycolysis occurs in the mitochondria.
Explanation: This statement is FALSE. Glycolysis occurs in the cytoplasm outside the mitochondria. It is a series of reactions that do not require the presence of organelles such as mitochondria.
Statement 3: Glycolysis is the first step in both aerobic and anaerobic respiration.
Explanation: This statement is true. Glycolysis is a common pathway in both aerobic and anaerobic respiration. After glycolysis, in aerobic respiration, the pyruvate produced enters the mitochondria for further breakdown through the Krebs cycle and the electron transport chain. In anaerobic respiration, under oxygen-limited conditions, fermentation occurs instead of entering the mitochondria.
Statement 4: Glycolysis produces 2 ATP, 2 NADH, and 2 pyruvate.
Explanation: This statement is true. During glycolysis, a total of 2 ATP molecules, 2 molecules of NADH, and 2 molecules of pyruvate are produced. The ATP molecules are generated directly through substrate-level phosphorylation.
Therefore, the false statement among the given options is statement 2: Glycolysis occurs in the mitochondria.