Revising the heart Bill Indge

Revising the heart In your revision, you need to: Learn the facts Master examination technique Practise the skills L

Revising the heart Left atrium Left ventricle Right atrium Right ventricle Learning the facts

Revising the heart Left atrium Left ventricle Right atrium Right ventricle

Revising the heart Left atrium Left ventricle Right atrium Right ventricle Vena cava Pulmonary artery Aorta Pulmonary vein

Revising the heart Left atrium Left ventricle Right atrium Right ventricle Vena cava Pulmonary artery Aorta Pulmonary vein Right atrioventricular valve Left semilunar valve

Revising the heart Sinoatrial node (SAN) Atrioventricular node (AVN)

Revising the heart Atrioventricular node (AVN) Sinoatrial node (SAN) Bundle of His

Revising the heart

Introducing tariff values Look through your specification for the ‘stories’ you might be expected to tell. Use past papers to help you to decide how many marks a question on a particular topic is likely to be worth. Add one for luck. Summarise the topic in the appropriate number of bullet points.

Revising the heart Look through your specification for the ‘stories’ you might be expected to tell. The structure and function of the heart Myogenic stimulation of the heart and transmission of the subsequent wave of electrical activity Roles of the sinoatrial node, atrioventricular node and bundle of His

Revising the heart Use past papers to help you to decide how many marks a question on a particular topic is likely to be worth. Explain how a heart beat is initiated and coordinated. (6 marks) Add one for luck 7 marks

Revising the heart Controlling the heartbeat Sinoatrial node Myogenic and beats spontaneously Impulse spreads over surface of atria Atria contract, forcing blood into ventricles Delay at atrioventricular node Atria empty before ventricles contract Impulse goes to base of ventricles and ventricle contracts from base upwards Summarise the topic in the appropriate number of bullet points.

Revising the heart The table shows the pressures in the left atrium, left ventricle and aorta during a cardiac cycle. Pressure/kPa StageLeft atriumLeft ventricleAorta Give the number of one stage where: a)blood flows into the aorta b)The valve between the atrium and the ventricle is open

Revising the heart Left ventricle Aorta Left semilunar valve Give the number of one stage where blood flows into the aorta. For blood to flow from the left ventricle to the aorta, the pressure in the ventricle must be higher than the pressure in the aorta.

Revising the heart StagePressure/kPa Left atriumLeft ventricleAorta

Revising the heart Left atrium Left ventricle Left atrioventricular valve Give the number of one stage where the valve between the atrium and the ventricle is open. If the valve is open, the pressure in the left atrium must be higher than the pressure in the ventricle.

Revising the heart StagePressure/kPa Left atriumLeft ventricleAorta

Revising the heart Applying your knowledge AO2 Candidates should be able to (b) apply scientific knowledge and processes to unfamiliar situations. Remember: you may not have seen the wrapping before but you will be familiar with what is inside. The context may be new but the biology will be familiar.

Revising the heart A hole in the heart is caused when the wall between the right atrium and the left atrium does not close properly when the heart is developing. This leaves a hole through which blood can pass between the two atria. 1 Use your knowledge of pressure to explain why blood flows from the left atrium to the right atrium. 2 The blood in the right atrium of a person with a hole in the heart is different in its oxygen concentration from the blood in the right atrium of a healthy person. (a)In what way is it different? (b)Explain what causes this difference. 3 The blood pressure in the pulmonary arteries of a person with a hole in the heart is different from that in the pulmonary arteries of a healthy person. (a)In what way is it different? (b)Explain what causes this difference.

Revising the heart A hole in the heart is caused when the wall between the right atrium and the left atrium does not close properly when the heart is developing. This leaves a hole through which blood can pass between the two atria. The material used in this question is not on your specification. The question will contain all the information you need so read it carefully. The situation may be new but the biology will be familiar. It is about the heart and blood flow. So, don’t panic

Revising the heart Left atrium Right atrium Hole in the heart

Revising the heart 1 Use your knowledge of pressure to explain why blood flows from the left atrium to the right atrium. (2 marks) L R Blood flows from high pressure to low pressure; Blood pressure higher in left atrium;

Revising the heart 2 The blood in the right atrium of a person with a hole in the heart is different in its oxygen concentration from the blood in the right atrium of a healthy person. (a)In what way is it different? (1 mark) (b)Explain what causes this difference. (2 marks) L R (a)Has a higher oxygen concentration; (b)Mixed with blood from left atrium Which is coming from lungs;

Revising the heart 3 The blood pressure in the pulmonary arteries of a person with a hole in the heart is different from that in the pulmonary arteries of a healthy person. (a)In what way is it different? (1 mark) (b)Explain what causes this difference. (1 mark) L R (a)Has a higher pressure; (b)Contains additional blood from left atrium;

Revising the heart Check with your specification and learn what you need to learn Find some past papers and practise the skills Graphs, tables and data handling Applying your knowledge to new situations