Which Statement Below Characterizes Metabolic Pathways

Question

Which statement below characterizes metabolic pathways?  
A) They are random sequences of reactions.
B) They are always biosynthetic.
C) They are always degradative.
D) They are enzyme-mediated sequences of reactions.
E) They are always linear reactions.

Accepted Answer

Metabolic pathways are defined as enzyme-mediated sequences of reactions in living organisms. These pathways can either be biosynthetic or degradative, and they are highly regulated to maintain metabolic homeostasis. However, they are not random sequences of reactions nor are they always linear reactions.