GlycolysisAQA A-Level Biology: Mind map

Exam questions on Glycolysis

1. Glycolysis was investigated in a cell-free extract of yeast, supplied with glucose, ATP, ADP, NAD and inorganic phosphate, in a sealed tube containing no oxygen.
   Explain why glycolysis begins with the phosphorylation of glucose using ATP.2 marks
2. A biochemist measures the ATP and reduced NAD produced when glucose is converted to pyruvate in a cell-free extract, with all the enzymes and cofactors in excess.
   Explain how glycolysis gives a net gain of two ATP per glucose molecule.2 marks
3. The metabolic poison iodoacetate inhibits the enzyme that oxidises triose phosphate during glycolysis. Cultured human cells in which glucose is the only respiratory substrate are treated with iodoacetate and supplied with glucose and oxygen.
   Predict and explain the effect of iodoacetate on the concentration of triose phosphate and on the production of ATP and reduced NAD in the cells.3 marks