Which component of blood is responsible for oxygen transport?

• A. Plasma
• B. Platelets
• C. Hemoglobin in red blood cells
• D. White blood cells

Answer: (C)

The component of blood responsible for oxygen transport is hemoglobin, which is found in red blood cells. Hemoglobin is a specialized protein that binds oxygen molecules in the lungs and carries them through the bloodstream to tissues and organs in the body. Each hemoglobin molecule can bind up to four oxygen molecules, allowing for efficient oxygen transport.

Plasma is the liquid portion of the blood that serves primarily as a medium for transporting various substances, including nutrients, hormones, and waste products, but it does not play a direct role in oxygen transport. Platelets are cell fragments involved in the clotting process and do not contribute to oxygen transport. White blood cells are part of the immune system and help fight infections, but they also do not aid in carrying oxygen. Thus, hemoglobin in red blood cells is the key component specifically specialized for the transport of oxygen.