1a.To know how the heart adapts during exercise, an understanding of the cardiovascular system is necessary. The main function of the cardiovascular system is to maintain blood flow to all parts of the body. It contains blood and vessels. The first vessel is made up of the arteries and its function is to carry blood to the body. The second blood vessel is capillaries. Capillaries carry blood to the heart, which then pumps blood throughout the body. The four chambers of the heart allow the heart to pump blood throughout the body. The four chambers of the heart are the right atrium, left atrium, right ventricle, and left ventricle. During exercise, the body requires more oxygen to produce energy, which is why the lungs begin to ventilate more quickly than usual, oxygen is pumped throughout the body as it diffuses into the blood. When blood flows through the body to the heart, blood first enters the right atrium; here the blood is transported to the right ventricle. The right ventricle carries blood to the lungs to increase oxygen levels. This stage is known as pulmonary circulation...