His body showed a rejection reaction to the transplanted organ.

His single word triggered a chain reaction, and everything changed.

This chemical reaction is very dangerous.

She overreacted to his words.

Nuclear reactions are used for mass production of energy.

I was surprised by his overreaction.

These test results are showing unexpected outcomes.

We analyzed the data of the experimental group.

He has a deep interest in empirical science.

The experimenter analyzed the data in detail.