Florida Basic Recruit Training Program High Liability (First Aid) Practice Exam

What type of blood cell brings carbon dioxide back to the lungs?

1. White blood cells

2. Platelets

3. Red blood cells

4. Plasma

The correct answer is: Red blood cells

Red blood cells are responsible for transporting carbon dioxide back to the lungs. They contain hemoglobin, a protein that binds to oxygen in the lungs for delivery to the body’s tissues, and it also binds to carbon dioxide produced by cellular metabolism for transport back to the lungs. Upon reaching the lungs, carbon dioxide is expelled from the body when we exhale. This process is vital for maintaining proper acid-base balance in the body and ensuring that tissues receive the oxygen they need while removing carbon dioxide effectively. The other types of blood components do not play this role. White blood cells are primarily involved in the immune response, helping to fight infections. Platelets are crucial for blood clotting, preventing excessive bleeding from injuries. Plasma is the liquid component of blood, primarily serving as a transport medium for nutrients, hormones, and waste products, but it does not transport carbon dioxide directly to the lungs like red blood cells do.