...and if you did your own homework you would know the answer!
Take SummerWind's advice and research the two terms and read them over carefully and decide for yourself... after all you DO have both computer and Internet access.
Yes'...both of them are a complete mystery to me
the difference is in the very names. Bio-chemical is where it is chemicals in a living organism, and electro-magnetic is a combination of electrical and magnetic energy. How can you not see a difference simply in the names?