Which blood cell type plays a primary role in the human body's immune defense against pathogens and foreign bodies?

💡 Solution & Explanation

Leukocytes, commonly known as white blood cells, form an integral component of the immune system by identifying, attacking, and destroying pathogens and foreign antigens. Erythrocytes are specialized for oxygen transport, whereas thrombocytes facilitate blood clotting during vascular injury. Reticulocytes represent immature red blood cells released into circulation from bone marrow.