1. The major energy-generating step during glycolysis is(A)hexokinase(B)phosphofructokinase(C)glyceraldehyde-3-P dehydrogenase.(D)phosphoglycerate kinase.

6. Which one of the following statements is true about catabolic pathways?(A)They combine molecules into more complex and energy-rich molecules.(B)They belong to the reduction reaction.(C)They are usually coupled with anabolic pathways and generate energy in the form of ATP.(D)They do not need enzyme catalysts.