Protein

Metabolism. It forms enzymes that speed up the chemical reaction in the body. Support. It has structural function. For example, it forms keratin which makes up our hair and nails. Transport. It forms hemoglobin which carries red blood cells in our blood. Defense. It forms antibodies which prevent antigens from destroying cells and upsetting homeostasis. Regulation. It forms hormones. For example, insulin regulates the blood glucose level in our bodies. Motion. Actin and myosin are made up of protein. There are responsible for the contraction and relaxation of muscles.