Biotech\'s Dictionary of Biochemistry

"Biochemistry is the study of the chemistry of life, a bridge between biology and chemistry that studies how complex chemical reactions give rise to life. It is a hybrid branch of chemistry which specialises in the chemical process in living organisms. This article only discusses terrestrial biochemistry (carbon-and water-based) as all the life forms we know are on earth. Since life forms alive today are believed to have descended from the same common ancestor, they naturally have similar biochemistries, even for matters which would appear to be essentially arbitrary, such as the genetic code or handedness of various biomolecules. It is unknown whether alternate biochemistries are possible or practical."