This chemical reaction is very dangerous.

Coenzyme is a substance necessary to assist chemical reactions in the body.

He always helps me when I'm in trouble.

Whenever he is feeling down, I always help him.

He found out that there was a foreign object inside his body.

Chemotransmitters play an important role in the transmission of information between nerve cells.

Your cooperation is needed for this project.

I need you.

This chemical reaction is very dangerous.

This chemical reacts when heat is added.