It is not mandatory.
Energy because you need kenetic energy for collisions to take place
The statement is false as a generalization.
Chemical reactions can produce heat and energy but not all chemical reactions produce them. Exothermic reactions produce heat and energy (possibly in the form of photons/light), while endothermic reaction absorb them.
Exothermic reactions produce heat. Endothermic reactions take in heat from the surrounding area and get cold.
The entire cell and extra cellular matrix is subject to thousands of chemical reactions every second. These chemical reactions produce all of our energy, or movements, thoughts EVERYTHING that occurs in the body.
chemical reactions are going on in our bodies all of the time
Not ALL reactions are chemicals. When chemicals reacte with other chemicals it is called as chemical reactions.
in the liver
in the liver
in the liver
in the liver
in the liver