1. Red Blood Cells (Erythrocytes): These are the most abundant type of blood cell and are responsible for carrying oxygen from the lungs to the body's tissues and removing carbon dioxide from the tissues back to the lungs. Their distinctive red color comes from the protein hemoglobin, which binds oxygen.

2. White Blood Cells (Leukocytes): These are part of the immune system and fight infection by identifying and destroying pathogens (like bacteria, viruses, and fungi). There are several different types of white blood cells, each with a specific role in the immune response.

3. Platelets (Thrombocytes): These are the smallest type of blood cell and are essential for blood clotting. When a blood vessel is damaged, platelets clump together to form a plug, helping to stop the bleeding.

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