Changes

===Cardiovascular System===

===Cardiovascular System===

Blood, which has been oxygenated by the lungs, flows through the pulmonary vein to the left atrium of the heart and subsequently to the left ventricle from which it is ejected by the heart during ventricular systole. Oxygenated blood is then distributed to the different parts of the body via the aorta. The distribution of blood is controlled by vascular tone which dictates the degree of perfusion of capillary beds and therefore the amount of oxygen available to the various tissues. Carbon dioxide produced from cellular respiration is removed from the tissues and transported either attached to proteins, in solution or as bicarbonate via the venous system to the vena cavae and ultimately to the right atrium. The passage of venous blood is a product of blood flow, vascular valves and muscular and respiratory function. Carbon dioxide rich blood enters the right ventricle and is then pumped to the lungs via the pulmonary artery.

Blood, which has been oxygenated by the [[Lungs - Anatomy & Physiology|lungs]], flows through the pulmonary vein to the left atrium of the heart and subsequently to the left ventricle from which it is ejected by the heart during ventricular systole. Oxygenated blood is then distributed to the different parts of the body via the aorta. The distribution of blood is controlled by vascular tone which dictates the degree of perfusion of capillary beds and therefore the amount of oxygen available to the various tissues. Carbon dioxide produced from cellular respiration is removed from the tissues and transported either attached to proteins, in solution or as bicarbonate via the venous system to the vena cavae and ultimately to the right atrium. The passage of venous blood is a product of blood flow, vascular valves and muscular and respiratory function. Carbon dioxide rich blood enters the right ventricle and is then pumped to the lungs via the pulmonary artery.

===Integration===

===Integration===