Regulation of cardiac output

Question 1

Cardiac output

Answer 1

total volume of blood pumped by the ventricle per minute

Question 2

At rest cardiac output

Answer 2

5 L / min

Question 3

During exercise cardiac output

Answer 3

25 L / min

Question 4

Equation to determine cardiac output

Answer 4

Cardiac output (CO) = Stroke Volume (SV) X Heart rate (HR)

Question 5

Venous return

Answer 5

Total blood volume returning to the heart by vena cava into the atria

Question 6

Stroke volume

Answer 6

The blood volume ejected per beat from each ventricle

Question 7

Ventricular end diastolic volume

Answer 7

total blood volume in each ventricle at end of diastole

Question 8

Ventricular end systolic volume

Answer 8

Total blood volume in each ventricle at the end of systole

Question 9

How many bpm does the SAN produce?

Answer 9

around 100

Faster than resting heart rate

Question 10

Vagal activity

Answer 10

Dominates the SAN to keep the heart rate down to 60/70 bpm

Question 11

Heart is innervated by:

Answer 11

Sympathetic fibres- noradrenaline

Parasympathetic fibres- acetylcholine

Question 12

Myocardium innervated by

Answer 12

sympathetic nerve fibres

Question 13

Starling’s law

Answer 13

Shows the relationship between stroke volume and myocardial stretch
Enables heart to eject additional venous return, increasing stroke volume