Overview
This lecture covers the process of glycolysis, the first step in cellular respiration, including its key stages, products, and important definitions.
Steps of Glycolysis
- Glycolysis begins with one glucose molecule in the cell's cytoplasm.
- ATP donates two phosphate groups to glucose through phosphorylation.
- Glucose is split into two three-carbon molecules with attached phosphate groups.
- Phosphate groups are later removed from these molecules, generating ATP.
- Electrons are captured by NAD+, forming NADH during phosphate removal.
- The final products are two pyruvate molecules.
Key Products and Features
- Glycolysis produces a net gain of two ATP molecules.
- Two NADH molecules are generated, each carrying stored electrons.
- End products are two three-carbon molecules called pyruvate.
- Glycolysis is anaerobic, meaning it occurs without oxygen.
Key Terms & Definitions
- Glycolysis — the first stage of cellular respiration, breaking down glucose into pyruvate.
- Cytoplasm — the fluid inside a cell where glycolysis occurs.
- Phosphorylation — the addition of a phosphate group to a molecule.
- ATP (Adenosine Triphosphate) — the main energy carrier in cells.
- NAD+ / NADH — molecules that carry electrons during cellular respiration; NAD+ becomes NADH when it gains an electron.
- Pyruvate — the three-carbon end product of glycolysis.
- Anaerobic — a process that does not require oxygen.
Action Items / Next Steps
- Review the steps and products of glycolysis.
- Be prepared to define key terms related to glycolysis.