revising the heart bill indge. revising the heart in your revision, you need to: learn the facts...
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Revising the heart
In your revision, you need to:
Learn the facts
Master examination
technique
Practise the skillsL
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
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
Stage Left atrium Left ventricle Aorta
1 0.5 0.4 10.6
2 1.2 0.7 10.6
3 0.3 6.7 10.6
4 0.4 17.3 16.0
5 0.8 8.0 12.0
Give the number of one stage where:a) blood flows into the aortab) The valve between the atrium and the ventricle is open
Revising the heart
Left ventricle
Aorta
Left semilunar valve
Give the number of one stagewhere 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
Stage Pressure/kPa
Left atrium Left ventricle Aorta
1 0.5 0.4 10.6
2 1.2 0.7 10.6
3 0.3 6.7 10.6
4 0.4 17.3 16.0
5 0.8 8.0 12.0
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
Stage Pressure/kPa
Left atrium Left ventricle Aorta
1 0.5 0.4 10.6
2 1.2 0.7 10.6
3 0.3 6.7 10.6
4 0.4 17.3 16.0
5 0.8 8.0 12.0
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
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;
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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;