A Spiral Metabolic Sequence Can Best Be Described as One

Multiple Choice

A spiral metabolic sequence can best be described as one in which

A) the product of the first reaction is the starting material for the next reaction,and so on.
B) a series of reactions regenerates the initial reactant.
C) the various reactions have virtually no connection to one another.
D) the same set of enzymes progressively builds up or breaks down a molecule.
E) the same set of enzymes catalyses the same reaction in both the forward and reverse directions.