Unformatted text preview: right atria, and the blood goes to the lungs. The left atria is thinly muscled, the blood comes from the lungs, and it is pushed down to the left ventricle. The left ventricle is thickly muscled, the blood enters from the left atria, and is pushed into the systematic loop, which distributes the blood to the rest of the system. 5. Arteries are thickly muscled and have a relatively large diameter. They branch into arterioles. Veins are less muscled and have the largest diameter. Smaller veins are called venules. Capillaries are the smallest in diameter and have thin walls, and are very abundant. They form capillary beds. 6. The first form is 7%, dissolved in CO as plasma. The second is 23%, “in transit” in red blood cells. The third form is 70% dissolved as bicarbonate. 7. Breathing contracts the diaphragm and decreases pressure on the thoracic cavity, thereby increasing its volume. Rib expansion expands the volume of the thoracic as well....
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- Fall '07
- RNA, right ventricle, left ventricle, internal environment, left atria