Overview of the function of the CVS1 and CVS2

Question 1

What does cardiovascular system transport?

Answer 1

O2 and CO2
Nutrients
Metabolites
Hormones
Heat

Question 2

What side of heart pumps blood into pulmonary circulation?

Answer 2

right side of heart

Question 3

What side of heart is responsible for pumping blood into the systemic circulation?

Answer 3

left side

Question 4

How is the cardiovascular system flexible?

Answer 4

Pump can vary output
Vessels can redirect blood
Vessels can store blood

Question 5

Describe why pumps of heart are in series?

Answer 5

in parallel
output is equal and tissues don’t receive deoxygenated blood

Question 6

Describe how vascular beds are arranged?

Answer 6

in parallel
Allows regional redirection of blood
e.g. in exercise want more blood going to skeletal muscle

Question 7

Why are gut and liver in series?

Answer 7

so nutrients in gut to be metabolised in liver

Question 8

What is the name of the liver’s own blood supply that’s arranged in parallel?

Answer 8

portal system

Question 9

Why does skin receive 9% of total output but only using 2% of oxygen?

Answer 9

more blood to skin so heat can be lost from it

Question 10

Why do kidneys receive 20% output but only use 6% oxygen?

Answer 10

kidneys are acting as filter

Question 11

Why does heart receive 4% of cardiac output but uses 10% of oxygen?

Question 12

What is darcy’s law?

Answer 12

flow= difference in pressure/ resistance

Question 13

What is meant by pressure difference?

Answer 13

mean arterial pressure (average blood pressure in arteries) (left hand side pressure)- central venous pressure (blood pressure coming back) (left hand side pressure)

Question 14

Where is the higher pressure on sides of the heart?

Answer 14

high pressure on left- to pump blood to systemic circ
low pressure on right-to pump blood back to heart

Question 15

How is resistance determined?

Answer 15

controlled by radius cubed

Question 16

What acts ass taps in resistance?

Answer 16

arterioles

Question 17

Difference between arteries and veins?

Answer 17

arteries - carry blood away from heart

veins - carry blood towards heart

Question 18

Role of veins and venules?

Answer 18

capacitance vessels
blood storage
Veins and venules return blood to right side of heart

Question 19

Describe the meaning of fractional distribution of blood?

Answer 19

the proportion of blood that is in veins and venules versus the rest of your systemic circulation

Question 20

Features of aorta?

Answer 20

blood leaves heart from left side here
Elastic arteries
Wide lumen ( low resistance for blood to flow very easily from left ventricle into aorta and off to systemic circulation)
Thick elastic wall
Damp pressure variations

Question 21

What are the two elastic arteries in your body?

Answer 21

aorta and pulmonary trunk

Question 22

Features of arteries?

Answer 22

Muscular arteries
Wide lumen
Strong, thick, non-elastic wall
Low resistance conduit

Question 23

Features of arterioles?

Answer 23

Resistance vessels
Narrow lumen
Thick contractile wall
Control resistance and therefore flow
Allow regional redirection of blood

Question 24

Give features of capillaries?

Answer 24

Exchange vessels
Narrow lumen
Thin wall

Question 25

Give features of venules?

Answer 25

Capacitance vessels (2/3 body's blood) Wide lumen Thin, distensible wall Low resistance conduit and reservoir Allows fractional distribution of blood between veins and rest of circulation

Question 26

Blood flow?

Answer 26

blood is squeezed from the left ventricle out into the aorta aorta is an elastic artery and so during that ejection phase - the wall of aorta stretches out the blood will pass into muscular arteries and then into arterioles after arterioles, blood passes into very small capillaries deoxygenated blood returns to RHS of heart via veins and venules

Question 27

Pumps of heart?

Answer 27

pump on right- pumps to pulmonary circulation pump on left- pumps blood into systemic circulation

Question 28

Through what does deoxygenated blood return to right atrium through?

Answer 28

through the vena cava

Question 29

Functions of superior and inferior vena cava?

Answer 29

superior- returns blood from part of body above heart inferior - below heart

Question 30

How is deoxygenated blood pumped into pulmonary circulation?

Answer 30

deoxygenated blood will fill into the right ventricle then into pulmonary trunk- which bifurcates into a left and right pulmonary artery - where it's then pumped into pulmonary circulation. When blood has been oxygenated, it returns to the left atrium via the pulmonary veins. Oxygenated blood will then fill into the left ventricle and it will be pumped out into the aorta to go round the body again.

Question 31

What is the valve between the left ventricle and the aorta?

Answer 31

aortic valve

Question 32

What is the valve between the right ventricle and the pulmonary trunk?

Answer 32

pulmonary valve

Question 33

When are valves open and closed?

Answer 33

open when heart is in systole - blood squeezed out of ventricles unto aorta and pulmonary trunk closed when heart is in diastole- when heart chambers are filling up with blood

Question 34

Where is the tricuspid valve?

Answer 34

between right atrium and right ventricle

Question 35

Where is the mitral valve?

Answer 35

between LA and LV -only two cusps

Question 36

What are the jobs of the mitral and tricuspid valves?

Answer 36

to prevent regurgitation of blood from the ventricle back into the atrium

Question 37

What are chordae tendinae attached to?

Answer 37

papillary muscles- contract at same time as ventricles

Question 38

How do the valves open and close?

Answer 38

due to changes in pressure in heart. The chordae tendinae and papillary muscles are only there to stop valves from turning inside out