How are the opposing pathways of glycolysis and gluconeogenesis prevented from extensive futile cycling? a) The catabolic and anabolic pathways do not take place in the same part of the cell. b) Both pathways share the same reactions, which are close to equilibrium and therefore can go either way. c) The overall free-energy change always favors the anabolic pathway. d) Key enzymes are regulated in a coordinated and reciprocal manner. e) All of the enzymes in the two pathways are different.