Problem
Describe the path of an oxygen molecule from outside of the body to the working plantar muscles of a foot. Discuss all major structures through which this molecule travels. Describe the route that carbon dioxide travels from the plantar muscles to outside of the body. Include all major structures through which this molecule travels. Include what parts of the blood transport the gasses, the forms in which they travel and what forces help move blood, oxygen and carbon dioxide along the way. Discuss at least 3 features of the circulatory system that enable blood to "keep moving" and two forces that allow for the movement of these gasses into and / or out of the body.