He is suffering from a subacute illness.

This species has different characteristics depending on its subgroup.

This airplane flies at subsonic speed.

I learned about the reaction of nitrous acid in chemistry class.

Hypochlorous acid is a hypo compound of chlorine.

Cell biology is the study of the structure and function of cells, which are the basic units of life.

We have a responsibility to protect the biodiversity of the Earth.

I am very interested in marine biology.

The study of benthos is an important field in marine biology.

He is an expert in aerobiology, engaged in the study of microorganisms in the atmosphere.