This reaction occurs through a chemical process.

He is an expert in virology.

He has a deep interest in teratology.

I am majoring in embryology at university.

He is an expert in embryology, studying the developmental processes of many kinds of organisms.

The president makes the final decisions regarding the operation of the university.

I set aside time for study every day.

He is a world-renowned scholar.

He is majoring in Dutch studies.

He has a deep interest in literature.