Which components of the blood carry oxygen to and carbon dioxide away from the cells?

Red blood cells are specifically designed to carry oxygen from the lungs to the tissues of the body and transport carbon dioxide from the tissues back to the lungs for exhalation. This crucial function is primarily facilitated by hemoglobin, a protein within red blood cells that binds to oxygen molecules in the lungs, allowing for effective nutrient delivery throughout the body. Simultaneously, red blood cells pick up carbon dioxide produced by cellular metabolism, ensuring that it is removed from the body efficiently.

In contrast, white blood cells play a role in the immune system, defending against infections and foreign invaders. Platelets are primarily involved in clotting and preventing blood loss from injuries rather than in gas exchange. Plasma, the liquid component of blood, serves as a transport medium for nutrients, hormones, and waste products, but it does not carry oxygen or carbon dioxide in the same specialized manner as red blood cells. Therefore, the correct choice accurately identifies the component responsible for oxygen and carbon dioxide transport within the circulatory system.