Gradually you notice that the large chamber walls seem to be closing in. You hear a thundering boom, and the whole chamber vibrates as the valve slams shut above you. The cords, now rigid and strained, form a cage about you, and you feel extreme pressure. Obviously, the lower chambers of the heart are in a full-fledged _____5______. Then, high above on the right, the "roof" opens, and you are forced through another valve which has led you into a very large artery. As you are swept along in a huge artery(the largest artery in the body), the____6_____, you pass several branch-off points, but continue to careen (fall) along, straight down at a dizzying speed until you approach the artery feeding the small intestine. After entering this artery and passing through successively smaller and smaller subdivisions of it, you finally reach the smallest blood vessels the_____7_______. You watch with fascination as nutrient molecules move into the blood through the single layer of ______8______(look at power point notes) cells forming the capillary (blood vessel) wall. As you move forward and you begin to move superiorly (up) once again, you enter the huge_______9______, which returns blood from the lower part of the body to the_______10_______of the heart. From here, you move consecutively through the right chambers of the heart into the_______11______artery, which carries you to the _____12_____to get ______13______and then back to the left side of the heart again where you started