How is the study of simple molecules relevant to larger biological molecules?Watch
If its an undergraduate essay-type question then topics of discussion could be:
All the elements used will be the same as basic organic compounds, resulting in the same primary bonding interactions.
Hydrogen bonding is incredibly important in proteins and DNA so studying H-bonding in water may be helpful...
Understand important relationships - such as the relationship between bond distance and bond energy (so can use one to estimate the other)
Techniques used to characterise them (IR, NMR, X-ray crystallography) are similar (but much more complicated for biological molecules)
As I see it the crux is that a large biological molecule is just more complicated - the basic principles of the study of molecules is the same...