Starch has the role of supplying energy; proteins can constitute cells and tissues, and participate in material transportation, catalysis, immune function, regulatory function, and provision of energy. 1. Starch: Starch is composed of glucose polymers, its main function is to provide energy for life activities, and it is one of the main energy-supplying substances. 2. Proteins: Functions include constituting the structure of cells and organisms, material transportation, catalytic function, immune function and so on. (1) constitute the cell and organism structure: protein is an important component of various tissues and organs of the human body, is the main structural component of the cell. (2) Material transportation: hemoglobin is the carrier of oxygen to the whole body; apolipoproteins are used to transport lipids. (3) Catalytic function: a variety of enzymes can catalyze chemical reactions, the majority of enzymes are proteins. (4) Immune function: the immune molecules that protect the body are all proteins. (5) Regulatory function: it has the role of regulating the physiological activity of various organs in the body. (6) Provide energy: proteins can provide energy for the body’s physiological activities.