Chapter 13 Resource: Circulation and Immunity

Name Date ClassCopyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.1LaboratoryActivityHeart StructureCan you name the part of your body that is a muscle, works on its own without any reminderfrom you, pushes about five liters of liquid through your body each minute, relaxes for only abouthalf a second, and squeezes or contracts 70 to 100 times a minute? The organ described is thehuman heart.StrategyYou will observe the outside and inside of a cow or sheep heart to locate and label the partsof a heart.You will study the direction of blood flow through the heart.You will review the condition of blood on the right side of the heart as compared with theblood on the left side.Materials2 colored pencils (red and blue)dissecting pandissecting probeheart (sheep or cow)*narrow tongue depressors*coffee stirrers (alternative)ProcedurePart A—Outside of Heart1. Position your sheep or cow heart in a dissectingpan so that it matches Figure 1.WARNING: Wash hands thoroughly afterhandling heart.NOTE: Use the description below and thedirections of arrows in Figure 2 to helplocate each part of the heart. Use Figure 2to label each part as you identify it.2. The superior and inferior vena cava returnblood to the right side of the heart frombody organs. Locate and label the superiorand inferior vena cava. The pulmonaryvein returns blood to the left side of theheart from the lungs. Locate and label thepulmonary vein.3. Blood in veins enters the right and left atriums,two small chambers at the top of theheart. Locate and label the right atrium andleft atrium.4. Pumping action of the heart squeezesblood from the atriums into the right andleft ventricles, two large chambers at thebottom of the heart. Locate and label theright ventricle and left ventricle.Figure 15. Pumping action of the heart squeezesblood from the two ventricles. Blood leavesthe heart on the left side by way of anartery called the aorta. Locate and label theaorta, which carries blood to all body parts.Blood leaves the heart on the right side byway of another artery, the pulmonaryartery. Locate and label the pulmonaryartery, which carries blood to the lungs.Circulation and Immunity 9Hands-On Activities