The heart 1 The heart The heart 2 What you will learn about in this topic: 1. The heart 2. The heart as a double pump 3. The circulatory and pulmonary systems The heart 3 Learning objectives By the end of this presentation you should be able to: • Understand how the heart and the circulatory and plumonary systems work • Describe the heart as a double pump • Explain why systems are important to athletes The heart 4 The circulatory system The circulatory system involves the heart, blood vessels and blood itself. These are the three essential components the body needs to survive. The heart 5 The circulatory system is made up of two separate circuits that blood travels through: the pulmonary circuit and the systemic circuit. The heart 6 This is a double circulatory system and blood passes through the heart twice. The heart 7 The functions of the circulatory system Oxygen and nutrients are transported to parts of the body, while waste or toxic products are removed. The balance of nutrients keeps the body functioning properly. The heart 8 The body relies on these actions to stay alive. The circulatory system controls body temperature. The body is affected by changes to temperature, so keeping it in an acceptable range keeps the body functioning properly. The heart 9 The circulatory system also helps protect the body; antibodies in the blood fight disease and platelets help to clot the blood at the source of a cut to prevent other germs entering the body. The heart 10 Task 1 Create prompt cards by writing down the main functions of the circulatory system on A6 size cards. Make sure they are neat and concise. They will help you to revise later on! The heart 12 Aorta Superior vena cava Pulmonary artery Pulmonary veins Left atrium Right atrium Semi-lunar valve Mitral value Tricuspid value Septum Right ventricle Left ventricle The heart 13 On heart diagrams, red arrows usually denote the arteries, showing oxygenated blood. Blue arrows usually denote the veins, showing deoxygenated blood. The heart 14 Task 2 1. Draw a copy of the heart diagram and label it. 2. Show the flow of blood through the heart on your diagram. Use colour (red and blue) to show where the blood is oxygenated and deoxygenated. The heart 15 The heart as a pump The heart acts as a pump in the double circulatory system. The heart 16 When the heart beats (contracts) it is called systole. This action forces blood through the arteries around the body. When the heart relaxes it fills with blood returning from the veins. This is called the diastole or diastolic phase. The heart 17 The pulmonary circuit carries deoxygenated blood from the heart, from the right ventricle, to the lungs, via the pulmonary artery; the blood is then oxygenated (carbon dioxide is removed from the blood in the lungs). The heart 18 The heart 19 The oxygenated blood is then taken from the lungs, via the pulmonary vein, and taken to the left atrium of the heart (oxygen is taken up by the haemoglobin in red blood cells). The heart 20 The heart 21 The systemic circuit carries oxygenated blood from the heart, pumped from the left atrium to the left ventricle into the aorta, to the rest of the body so it can use the oxygen. The heart 22 The heart 23 Deoxygenated blood is then taken back from the body to the right atrium of the heart via the vena cava. The cycle then starts over again. The heart 24 The heart 25 The heart The heart has four chambers. The two atria collect blood and the two ventricles pump the blood out of the heart. The heart 26 Deoxygenated blood Oxygenated blood The heart 27 The right side of the body pumps deoxygenated blood (blood with no oxygen in it) to the lungs. Oxygenated blood The heart 28 The left side pumps oxygenated blood (blood with more oxygen in it) from the lungs to the rest of the body. Deoxygenated blood The heart 29 The septum divides the left and right sides of the heart so that oxygenated and deoxygenated blood do not mix. Septum The heart 30 The left ventricle wall is thicker than the right side. It is more developed as it pumps blood further around the body. Left ventricle The heart 31 Sets of valves are positioned in the heart to stop the backflow of blood. Semi-lunar valve The heart 32 Task 3 Draw a diagram in your work book showing the pulmonary and systemic systems. Clearly label your diagram. The heart 33 Task 4 As a class, discuss why you think the circulatory system is important to sportspeople. The heart 34 Exam questions 1. Which of the following best describes the pulmonary circuit? A. Heart – pulmonary arteries – lungs – pulmonary vein – heart B. Heart – aorta – lungs – pulmonary vein – heart C. Heart – pulmonary arteries – capillaries – lungs – pulmonary vein – heart D. Heart – pulmonary arteries – lungs – vena cava – heart The heart 35 What you have learnt in this topic: 1. The heart 2. The heart as a double pump 3. The circulatory and pulmonary systems 4. Functions of the circulatory system The heart 36 Learning objectives You should now be able to: • Understand how the heart and the circulatory and pulmonary systems work • Describe the heart as a double pump • Explain why systems are important to athletes