Initially, I thought problems on how the brain works to be the most interesting. But it was necessary to be practical and concentrate on less obscure matters when I entered Washington State College. Besides, there were no courses given in neurobiology.
Enzymologists usually study the initial rates of reactions measuring product formation as a function of substrate concentration or other variable. Cell biologists are more likely to want to know the effect of a change on the steady state behavior of a complex system.