The origin of replication (also called the replication origin) is a particular sequence in a genome at which replication is initiated.
It is the interaction of two or more substances, resulting in chemical changes in them. Chemical reactions take place when some kind of energy is supplied to them. The supplied energy may be in the form of heat, light or mechanical shaking for proper contact between the reactant molecules or electricity.
So letâs say, other molecules i.e enzymes, proteins, etc. are like plants, and the phosphates are like little suns, that radiate energy for the plants to function. Most chemical reactions require external energy(like and ice cube melting, which requires heat/infrared radiation), to induce a reaction and ATP does that.