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.
Best Answer: By definition exothermic reactions release heat, and endothermic reactions take in heat. When you have a combustion reaction, there's always a lot of heat produced (think if burning gasoline) and clearly the air around you doesn't get colder (not endothermic), so it must be exothermic.hen you have a combustion reaction, there's always a lot of heat produced (think if burning gasoline) and clearly the air around you doesn't get colder (not endothermic), so it must be exothermic.