Answer:
7. D
8. D
Explanation:
7. One of the most important functions of iron is the transportation of oxygen to the blood. Iron’s main purpose is to carry oxygen in the hemoglobin of red blood cells throughout your body so your cells can produce energy.
8. A network of tiny capillaries connects the arteries and veins. Though tiny, the capillaries are one of the most important parts of the circulatory system because it’s through them that nutrients and oxygen are delivered to the cells.
