2 The Heart Muscular pump, about the size of a clenched fist Made up of a special muscle called MyocardiumThis can contract continuously without getting tiredMain purpose is to drive blood through the arteriesThis delivers blood to the working muscles and other tissues.
3 Task…Find a picture of a blank heart (that is suitable to annotate) and upload it to a blank document.Then do some light background research on the different labels of the heart including…Structure of the cardiovascular system- heart:AtriaVentriclesBicuspid valve and tricuspid valveAortic valve and pulmonary valveAorta and vena cava – superior and inferiorPulmonary vein and pulmonary artery
4 The Heart continuedThe Heart sits in a twin layered sac known as the PericardiumFilled with pericardial fluidPrevents friction as your heart beats.
5 The Heart continued Epicardium (Outer) The heart wall has 3 layersEpicardium (Outer)Myocardium (middle layer and most of the heart wall)Endocardium (The inner layer)
6 Ventricles Atria Lower chambers of the heart Upper chambers of the heartReceive blood.Right Atrium – receives deoxygenated blood from the body (Via the Vena Cava)Left Atrium – receives oxygenated blood from the lungs (Via the pulmonary Vein)VentriclesLower chambers of the heartThey have thicker walls and are strongerJob is to pump the bloodRight Ventricle pumps blood to the lungs (pulmonary circulation)Left ventricle pumps blood to the body (systemic circulation)
7 Valves Tricuspid Valve Bicuspid Valve Aortic Valve Pulmonary Valve Also known as the mitral valveAortic ValvePulmonary ValveAll valves make sure that the blood flows in one direction, and there is no back flowChordae TendineaeCord like tendons that connect to the tricuspid and bicuspid valvesEnsure the valves stay the right way round and keep the blood flowing in the same direction.
8 Aorta and Vena Cava The largest Artery is the Aorta The largest vein is the Vena CavaCarries blood directly into the heart from the bodySuperior vena cavabrings blood from the upper bodyInferior Vena CavaBrings blood from the lower body.The largest Artery is the AortaCarries oxygenated blood directly out of the heart to the body tissues
9 Pulmonary Circulation Pulmonary ArteryCarries deoxygenated blood from the heart to the lungs.It is the only artery that carries deoxygenated bloodPulmonary VeinCarries oxygenated blood from the lungs to the heartIt is the only vein that carries oxygenated blood.
10 The Heart = Double pumpTo describe the flow of blood around the heart and the body, you will need to mention that the heart is made up of two pumpsPulmonary circulationPumps blood to and from the lungsSystemic circulationPumps blood around the body
11 Passage of blood flowBlood flows into and out of the heart and around the body in one direction.The heart is split into two distinct pumps by the Septum.This makes sure that the oxygenated and deoxygenated blood don’t mix.When describing the passage of blood flow around the heart, it is best to use a diagram and start on the right side of the heart.
12 The right side of the heart Blood enters the heart (when it is relaxed) via the vena cavae,It goes into the right atriumThe right atrium contracts and the blood goes through the tricuspid valve and into the right ventricleThe right ventricle contracts and the blood is pushed out of the heart through the semi lunar or pulmonary valve and into the pulmonary arteryThe pulmonary artery carries the blood to the lungsThe heart relaxes and the valves close to stop back flow of the bloodIn the lungs, the blood becomes oxygenated, and begins it’s journey back to the heart.
13 The Left side of the heart The heart is relaxed, and this allows blood to enter the left side of the heart from the pulmonary veinIt enters the left atriumThe left atrium contracts and pushes blood through the bicuspid valve and into the left ventricleThe left ventricle has a very strong muscular wall and contracts very strongly. This closes the bicuspid valve to prevent backflow, and pushes the blood through the aortic valve and into the aorta. This is the largest artery and splits taking the blood to different areas of the bodyThe heart contracts and the aortic valve closes, preventing back flow of the blood.
14 Terminology Heart rate (H.R.) Stroke Volume (S.V.) Cardiac Output The amount of times the heart beats in a minute.Usually measured in beats per minute (b.p.m.)Stroke Volume (S.V.)The amount of blood leaving the left ventricle in one beat.Normally measure in mililitresCardiac OutputThe amount of blood leaving the heart in one minuteNormally measured in litres/minuteCardiac Output = Stroke Volume x Heart Rate
15 Task…Finish off annotating and labelling the various parts of the heart: