Which statement about glycolysis is true?

Which statement about glycolysis is true?

• A. It occurs in the cytoplasm
• B. It occurs in the mitochondria
• C. It requires oxygen to proceed
• D. It uses water as a reactant

Answer: (A)

Glycolysis takes place in the cytoplasm. It’s the first step of glucose breakdown and does not require oxygen, so it can proceed under anaerobic conditions. During glycolysis, one glucose is split into two pyruvate molecules, yielding a net gain of 2 ATP and 2 NADH per glucose. The mitochondria aren’t involved in glycolysis itself; they become important in later steps (like the citric acid cycle and oxidative phosphorylation) that rely on oxygen to harvest more energy. Also, water is produced in a step of glycolysis (2-phosphoglycerate to phosphoenolpyruvate releases water), not consumed, so using water as a reactant isn’t correct.

Glycolysis takes place in the cytoplasm. It’s the first step of glucose breakdown and does not require oxygen, so it can proceed under anaerobic conditions. During glycolysis, one glucose is split into two pyruvate molecules, yielding a net gain of 2 ATP and 2 NADH per glucose. The mitochondria aren’t involved in glycolysis itself; they become important in later steps (like the citric acid cycle and oxidative phosphorylation) that rely on oxygen to harvest more energy. Also, water is produced in a step of glycolysis (2-phosphoglycerate to phosphoenolpyruvate releases water), not consumed, so using water as a reactant isn’t correct.