Explain how a chemical reaction occurs using the following terms Reactant
Product
Activation energy
Bond
Endothermic
Exothermic
Rate

For a chemical reaction to occur, activation energy is required. Using the activation energy, reactants form products by breaking bonds which require energy. This type of reaction is an endothermic reaction. When products are formed, bonds are formed back by releasing energy. This type of reaction is an exothermic reaction. When activation energy is used for a reaction, a catalyst is not required. Adding a catalyst to the reaction causes the rate of reaction to increase.

Neurotransmitters are messengers responsible for communication between neurons. they are released from synaptic vesicles and are received by receptors.  the communication is referred to as neurotransmission. the following statement is true about neurotransmitters: a. they're stored in synaptic vesicles in the axon.