- Arteries are thick, muscular vessels that carry blood away from the heart. Because arteries are elastic, they expand during systole. Their contraction during diastole propels the blood through the body.
- Arterioles are the smallest arteries and have rings of muscle around them to serve as valves. Arterioles control blood flow into the capillaries by relaxing or contracting the rings of muscle. They also control blood pressure in the arteries.
- Arteries and arterioles help maintain blood flow by maintaining blood pressure.
In the previous section students learned that the pumping heart moves blood throughout the circulatory system. In this section students explore the structure and function of the arteries and arterioles that carry the blood. Students determine pulse rates and feel the blood being pumped through their own arteries. They build models of healthy and diseased arteries and perform a simulated cut-and-paste coronary artery bypass procedure. Students explore some problems associated with atherosclerosis and discuss good cardiovascular health habits. They discuss the important role of arteries and arterioles in maintaining blood pressure. Students investigate how arteries and arterioles help maintain the body's blood pressure by regulating the blood flow from the heart to the cells.
arteries, arterioles, atherosclerosis, capillaries, coronary arteries, heart attack, pulmonary arteries
Activity 3-1: Blocked Arteries
- Resources 1 and 2
- Activity Report
- Clear rubber tubing or toilet paper rolls; Scissors; Water; Paste; Markers; Cotton or clay
Activity 3-1: Blocked Arteries
- Activity Report Answer Key
- Materials for constructing models of arteries
- American Heart Association slides of occluded arteries
- “Eat Smart” video produced by MacNeil-Lehrer (optional)
- Photos of occluded arteries (optional)
- Diagram or model of the circulatory system showing the locations of the major arteries
See Activity 3-1 in the Student Edition,
Display the models students built in Activity 1-1. Display a siphon pump from Activity 2-2.
Make clay or putty with a light yellow color to represent fats and cholesterol.
Art Students can construct models. They can cut and paste a model of a bypass procedure.
Math Students can design and solve pressure/ volume problems.
Language Arts Students can write a story about moving through the circulatory system, paying special attention to the pulse caused by each heartbeat and the components of the blood.
The walls of arteries have many elastic fibers that help maintain a smooth flow of blood. These fibers are stretched during systole, which stores some of the energy. Then during diastole, the elastic fibers propel the blood forward using this stored energy. This ensures an even flow of blood. These elastic fibers also help the arteries withstand the high pressures they are under.
The walls of arteries also contain smooth muscle fibers that control the distribution of blood to the different parts of the body by altering their diameter and changing their resistance.