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

Which type of blood cell is responsible for carrying oxygen from the lungs to the body?

1. White blood cells

2. Platelets

3. Red blood cells

4. Plasma

The correct answer is: Red blood cells

Red blood cells are specifically designed for the transportation of oxygen from the lungs to various tissues throughout the body. These cells contain a protein called hemoglobin, which binds to oxygen molecules in the lungs. When red blood cells travel through the bloodstream, they release oxygen to the cells and tissues that require it for metabolic processes. This function is crucial for sustaining cellular respiration, which is how cells generate energy. In contrast, white blood cells serve a different purpose; they are primarily involved in the immune response and help protect the body against infections. Platelets play a key role in blood clotting and are essential for wound healing, but they do not carry oxygen. Plasma, the liquid component of blood, transports nutrients, hormones, and waste products but does not play a direct role in oxygen delivery. Therefore, red blood cells are the critical component responsible for oxygen transport in the circulatory system.