An enzyme doesn't break apart a specific substrate because it wants to, it's amino acids form a electromagnetic environment that makes the substrate breaking apart energetically favorable because of its 3-D shape and the electromagnetic charge positions.
Once again however I think you are looking for something metaphysical.. purpose rather than function......you wont find some deep “purpose” by looking at biological molecular interactions, just mechanical functions.
Clothing... functions even moves and has purpose but it is not alive..
Is the human body merely clothing to the spirit?..
Are all "bodies" of living organisms clothing?... i.e. to types of spirits..
The old observer problem of "What is life?".. and that answered.. "What is death?".. or vice versa..