Unit 2 Physiology and Health 1. Structure of the heart Higher Human Biology Unit 2 Physiology and Health 1. Structure of the heart

What do I remember? What is tissue fluid? How is tissue fluid different to plasma? What is the purpose of tissue fluid? What is the lymphatic system? What is lymph? Extra: what happens when the lymphatic system goes wrong?

What do I need to know? What is the structure of the heart? What is the path of blood through the heart? What is the definition of cardiac output? How is cardiac output calculated?

What is the structure of the heart? Revision Right Left Aorta Vena cava Pulmonary vein Pulmonary artery Left atrium Right atrium Semi lunar valve AV Valve Left ventricle Thick muscular wall Right ventricle Thinner muscular wall

Heart Rate (HR) Revision Number of times heart beats in one minute Normal values around 72bpm Normal range is between 60-90

Stroke Volume (SV) Volume of blood ejected by each ventricle during contraction Normal values are around 70ml Calculate

Cardiac output = Heart rate x stroke volume The volume of blood pumped by each ventricle per minute and is the function of two factors: Heart rate and Stroke volume The left and right ventricles pump the same volume of blood through the aorta and pulmonary artery. Cardiac output = Heart rate x stroke volume

Cardiac output calculation At rest: Heart Rate (HR) = 72bpm Stroke Volume (SV) =70ml Cardiac output = HR X SV = 72 x 70 = 5040 ml/min = 5.04 l/min

Cardiac Output varies between individuals and depends on their physical fitness and level of activity For example, the heart of a highly trained athlete can pump 30-35 l/min Most non-athletes can only achieve a max of 20 litres/min

What do I know What is the structure of the heart? What is the path of blood through the heart? What is the definition of cardiac output? How is cardiac output calculated?

Activities Listen to heart beat using stethoscope Measure heart rate using pulsometer Dissect heart Questions p165 No’s 1 - 3