The Cardiovascular System

What The Cardiovascular System covers

The Cardiovascular System is examined in Component 01, Physiological factors affecting performance. It covers heart rate, stroke volume and cardiac output at rest, the cardiac cycle and conduction system, cardiac responses to exercise and recovery, the vascular shunt mechanism and venous return and heart rate regulation.

The 5 subtopics

Each one has its own page.

• Heart rate, stroke volume and cardiac output at restResting heart rate, stroke volume and cardiac output, the equation that links them, the thicker left ventricle, worked pulse and cardiac output calculations, and why trained and untrained performers share a resting cardiac output.Open →
• The cardiac cycle and conduction systemDiastole, atrial systole and ventricular systole, the timing of a 0.8-second cycle, the myogenic heart, the sinoatrial node, atrioventricular node, bundle of His and Purkinje fibres, and the valves that stop backflow.Open →
• Cardiac responses to exercise and recoveryThe anticipatory rise, heart rate in submaximal and maximal exercise and recovery, estimated maximum heart rate, the stroke volume plateau, Starling's law, trained and untrained maximal cardiac output, and worked calculations for a runner and a cyclist.Open →
• The vascular shunt mechanismRedistribution of cardiac output to skeletal muscle, the vasomotor centre and its receptors, sympathetic stimulation, arterioles and pre-capillary sphincters, blood flow to the brain and skin, and why a large meal before exercise is avoided.Open →
• Venous return and heart rate regulationVenous return and the skeletal muscle pump, respiratory pump, pocket valves, smooth muscle and gravity, the dizzy rower, the cardiac control centre, sympathetic and parasympathetic control, chemoreceptors, baroreceptors, adrenaline and intrinsic factors.Open →

What you need to know

Answer each one before you reveal it.

Take The Cardiovascular System further

The same content, four other ways.

Commonly confused

Pairs that lose marks when they are blurred together.

• Systole vs Diastole

  Systole: the contraction phase of the heartbeat when blood is ejected. Diastole: the relaxation phase of the heartbeat when the chambers fill.

• SA node vs AV node

  SA node: the pacemaker tissue in the right atrium wall that starts each beat. AV node: the junction tissue that delays the impulse before it reaches the ventricles.

• Stroke volume vs Cardiac output

  Stroke volume: the amount of blood the left ventricle ejects per beat. Cardiac output: the amount of blood the left ventricle ejects each minute.

Questions from this topic

Each one with the model answer underneath.

1. 1

   Define heart rate and give a typical resting value.

   Model answer

   Heart rate is the number of times the heart beats per minute. A typical resting value for an untrained adult is about 70–72 bpm.

2. 2

   Define stroke volume and give a typical resting value.

   Model answer

   Stroke volume is the volume of blood pumped out of the left ventricle in each contraction. A typical resting value is about 70 ml.

3. 3

   Define cardiac output and give a typical resting value.

   Model answer

   Cardiac output is the volume of blood pumped out of the left ventricle each minute. The typical resting value is about 5 L/min.

4. 4

   State the equation linking cardiac output, stroke volume and heart rate.

   Model answer

   Cardiac output equals stroke volume multiplied by heart rate. The equation is Q = SV × HR.

5. 5

   Why does the left ventricle have a thicker wall than the right ventricle?

   Model answer

   The left ventricle pumps oxygenated blood through the aorta to the whole body. The thicker muscular wall generates the higher pressure this needs.

6. 6

   A performer's pulse is counted as 18 beats in 15 seconds. What is the resting heart rate?

   Model answer

   The resting heart rate is 72 bpm. The count × 4 gives 18 × 4 = 72 beats per minute.

What is inside Levo

Six ways to work the same material.

The Cardiovascular System revision questions

What does The Cardiovascular System cover in OCR A-Level Physical Education?

5 subtopics: heart rate, stroke volume and cardiac output at rest, the cardiac cycle and conduction system, cardiac responses to exercise and recovery, the vascular shunt mechanism and venous return and heart rate regulation. Each one has its own page with questions and model answers.

How is The Cardiovascular System organised?

By the OCR H555 specification, subtopic by subtopic, so it matches the order you are taught it in.