The reaction that absorbs energy from its surroundings is known as an endothermic reaction. In such reactions, the total enthalpy of the system increases as energy (usually in the form of heat) is absorbed. These reactions are characterized by a drop in temperature of their surroundings, making them feel colder. Endothermic reactions are vital in various biological and chemical processes, such as photosynthesis, where plants absorb sunlight to convert carbon dioxide and water into glucose and oxygen. Understanding these reactions is crucial in fields like thermodynamics and chemistry.