Heart Matter

Activity 4.3.1: The Heart of the Matter |

Introduction

Movement by muscles pulling on bones would not be possible if blood did not supply this tissue with the key resource, oxygen. The flow of blood around the body ensures that essential nutrients are delivered and wastes are moved away for disposal. At the center of this system is the amazing pump, the human heart.

The force your heart exerts at each pump is about the equivalent of your squeezing a tennis ball. Not exactly easy, is it? In fact, the muscle in the heart works twice as hard as the leg muscles of a person who is sprinting. We have looked in depth at skeletal muscle and how this tissue works with the nervous system to contract and pull on bone. In this lesson, you will take a look at the types of muscle at work in the cardiovascular system. What if you had to think every time your heart needed to beat? What if the signal had to make its way to your brain, be processed and make its way back to the heart to cause a contraction? Most likely, you would not last too long. For this reason, contraction of your heart muscle isinvoluntary. It happens (or at least it should) without yourever having to think about it.

A series of tubes, or vessels, serve as the highways for the transportation of blood. Arteries are responsible for carrying blood away from the heart and veins are responsible for returning blood back to the heart. By looking at how blood is pumped in and out of the heart, you will begin to see how thestructure of arteries and veins relates to the stress each vessel has to endure.

In PBS, you viewed the main structures inside the heart by completing a dissection and you monitored heart function with probes and sensors. In this activity, you will review the basic structure of the heart as well as identify the major blood vessels that bring blood in and out of the heart’s chambers. Finally, you will really get to the “heart of the matter” and create a clay heart for your beloved...