The chemicals that send instructions to cells are:

Chemicals are used for the communication between two cells whether the communication is from surface to surface or direct or through receptors. So the chemicals that send instructions to cells are A, T, C, and G in DNA which is four nucleotide bases called as adenine, thymine, cytosine and guanine.

Processes above and be sure to mention the movement of electrons and energy as the carbon atom moves from one reaction to another.