Cardiovascular System

Question 1

Define cardiac output

Answer 1

The amount of blood ejected out of the heart per minute (Q = HR x SV)

Question 2

What does the pulmonary circuit do?

Answer 2

Carries deoxygenated blood to the lungs & oxygenated blood back to the heart

Question 3

What does the systemic circuit do?

Answer 3

Carries oxygenated blood to the body & deoxygenated blood back to the heart

Question 4

Define stroke volume

Answer 4

the volume of blood ejected from the left ventricle per beat and occurs during ventricular systole

Question 5

Why does heart rate increase just before exercise?

Answer 5

Anticipatory rise due to adrenaline release

Question 6

Define heart rate

Answer 6

The numbers of beats per minute (measured in bpm)

Question 7

What does myogenic mean?

Answer 7

It is the hearts capacity to generate it’s own electrical impulse

Question 8

What does SA node stand for and where can it be found?

Answer 8

Sino-atrial node - located in the right atrial wall

Question 9

What does the SA node do?

Answer 9

Generates the electrical impulse causing atria to contract

Question 10

What does AV node stand for and what does it do?

Answer 10

Atrio-ventricular node: collects the impulse sent from the SA node and delays the impulse by 0.1 seconds

Question 11

Why does the AV node delay the electrical impulse?

Answer 11

To allow both atria to finish contracting

Question 12

After the AV node releases the electrical impulse, where does it travel next?

Answer 12

Down the Bundle of His

Question 13

Where is the bundle of His located?

Answer 13

in the septum of the heart

Question 14

What is cardiac diastole?

Answer 14

Relaxation of the cardiac muscle

Question 15

What is cardiac systole?

Answer 15

Contraction of the cardiac muscle

Question 16

What is the common way to calculate someone’s HRmax?

Answer 16

220 - age

Question 17

What is venous return?

Answer 17

return of blood to the right atria through the veins

Question 18

What is the difference between sub-maximal and maximal exercise?

Answer 18

Sub-max = lot to moderate intensity exercise below the anaerobic threshold

Maximal = high intensity exercise above the aerobic threshold

Question 19

What is Starling’s law?

Answer 19

It shows how stroke volume is dependant upon venous return

Question 20

What is an average HR at rest?

Answer 20

70-72 bpm

Question 21

What is an average SV at rest?

Answer 21

70 ml

Question 22

What is an average cardiac output at rest?

Answer 22

5 l/min

Question 23

Where would you find the cardiac control centre (CCC)?

Answer 23

Medulla Oblongata in the brain

Question 24

What are the 3 sources of information that determine the action of the cardiac control centre?

Answer 24

Chemoreceptors, proprioceptors and baroreceptors

Question 25

How can you tell the difference between the sympathetic and parasympathetic nervous system?

Answer 25

Sympathetic = activated in response to exercise

Parasympathetic = activated during recovery from exercise

Question 26

Which blood vessel has smooth muscle in it’s wall as well as pocket valves to prevent backflow?

Answer 26

Veins

Question 27

What is blood pooling?

Answer 27

The accumulation of blood in the veins due to gravity and lack of venous return due to stopping exercise

Question 28

How can an athlete prevent blood pooling?

Answer 28

Perform an active recovery

Question 29

Describe the vascular shunt mechanism

Answer 29

1. Control centres in the medulla oblongata detect changes due to exercise
2. Activation of sympathetic nervous system
3. Pre-capillary sphincters constrict to organs and dilate to working muscles

Question 30

What part of the brain controls the vascular shunt mechanism?

Answer 30

Vasomotor Control Centre (VCC)

Question 31

Where does the Vasomotor Control Centre receive information from?

Answer 31

Chemoreceptors and baroreceptors