Hemoglobin is a protein present in the blood of animals, especially in the Red Blood Cells (RBC's) of vertebrate. They are used in transporting oxygen to the tissues.
This hemoglobin creates bond with the oxygen (travelling through tissues) which is highly unstable. When it is in oxygenated state, it has bright red color, while in reduced state has purplish blue color.
Lack of oxygen in hemoglobin, can cause hazardous diseases like the sickle cell anemia.
This particular disease is caused due to lack of oxygen.
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