What type of blood cell is primarily responsible for oxygen transport?

Erythrocytes, commonly known as red blood cells, are primarily responsible for the transport of oxygen in the bloodstream. They contain hemoglobin, a specialized protein that binds to oxygen in the lungs and releases it in tissues throughout the body. The structure of erythrocytes, which are biconcave and lack a nucleus in their mature form, enhances their ability to carry oxygen efficiently. This design increases their surface area for gas exchange and allows for flexibility as they navigate through the narrowest capillaries.

The other cell types mentioned play different roles in the body. Leukocytes are involved in the immune response and protect the body against infections. Platelets are crucial for blood clotting and wound repair by aggregating at sites of vascular injury. Myocytes, or muscle cells, are responsible for contraction and movement but do not play a role in oxygen transport. Thus, erythrocytes are the key players in transporting oxygen, making them essential for maintaining cellular respiration and overall metabolism.