Essence (Jing) is a fundamental material of the human body and the material basis for various physiological functions of the human body. The congenital essence is received from one's parents, and is stored in the kidney; it is also known as "the prenatal essence", serving to promote the growth, development maturity, and reproduction of the body, thus the congenital essence is also called the "reproductive essence. The acquired essence is derived through the functions of the Zang-Fu organs from the nutritive substance of food and drink to nourish the body. In turn, it serves as the material basis for the functional activities of the Zang-Fu organs. Consequently,.
