Antigens Proteins found on the surface of cells. Bacteria in your body have certain antigens your body knows to desetroy. Hemoglobin Proteins in your blood stream the bring oxygen to your body’s cells. When you travel to higher altitudes your body must mass produce hemoglobin to ensure your cells get enough oxygen. Antibodies These proteins target and destroy foreign invader cells in your body. Protease Different levels of this protein in your body determine your metabolism. Kinesin This is a motor protein. It helps you with movement. Helicase Unzips or separate a DNA strand so the instructions can be read.