Hemoglobin is a type of protein. It is found in red blood cells in the human body. It helps in transporting oxygen in our body. The function of hemoglobin is to deliver oxygen to every part of the human body. As the amount of hemoglobin in the blood decreases, so does the supply of oxygen. Anemia is an important component of blood in our body, red blood cells , and the lifeblood of red blood cells is hemoglobin. The function of this hemoglobin is to transport oxygen from the lungs to the body cells. Again, we need oxygen to survive. When the level or amount of hemoglobin in the blood decreases for any reason, that condition is called anemia.