overview and function of the cardiovascular system

Question 1

what is the function of the cardiovascular system?

Answer 1

acts as a bulk flow system which transports things around the body

Question 2

what are examples of things that the cardiovascular system transports around the body?

Answer 2

• oxygen and carbon dioxide
• nutrients
• metabolites
• hormones
• heat

Question 3

how is the cardiovascular system flexible?

Answer 3

• pump can vary output
• vessels can redirect blood
• vessels can store blood

Question 4

are pumps in the cardiovascular system in series or parallel and what does this mean?

Answer 4

series - output must be equal (left and right side of the heart)

Question 5

are vascular beds in series or parallel, and what does this mean?

Answer 5

parallel - all tissues gets oxygenated blood and allows regional redirection of blood

Question 6

are all vascular beds in parallel?

Answer 6

no, some are in series

Question 7

what are examples of vascular beds that are in series?

Answer 7

• hypothalamus and anterior pituitary
• gut and the liver

Question 8

why are some vascular beds in series?

Answer 8

allows blood to flow directly from one place to where it next needs to go, such as carrying nutrients from the gut to the liver

Question 9

how should the percentage of cardiac output compare to the percentage of oxygen consumption?

Answer 9

they should be about the same

Question 10

what are examples of organs where the cardiac output and oxygen consumption are not in balance?

Answer 10

• kidneys (more cardiac output than oxygen consumption)
• skin (more cardiac output than oxygen consumption)
• ♡ (more oxygen consumption than cardiac output)

Question 11

why do the kidneys receive a greater cardiac output than oxygen consumption?

Answer 11

they filter the blood

Question 12

why does the skin receive a greater cardiac output than oxygen consumption?

Answer 12

thermoregulation, blood is sent there to cool it and maintain body temperature

Question 13

why does the heart have a greater oxygen consumption than cardiac output?

Answer 13

each time it contracts it cuts of its own blood supply

Question 14

how can blood be redirected during exercise?

Answer 14

altering the resistance of different vessels

Question 15

what formula relates flow to pressure and resistance?

Answer 15

Question 16

how is flow proportional to the difference in pressure?

Answer 16

directly proportional

Question 17

how is flow proportional to the resistance?

Answer 17

inversely proportional

Question 18

What is the formula to describe pressure difference?

Answer 18

mean arterial pressure - central venous pressure

Question 19

what is resistance controlled by?

Answer 19

the radius of a vessel

Question 20

what is the relationship between resistance and the radius of a vessel?

Answer 20

inversely proportional

resistance = to the radius to the power of 4

Question 21

what happens to mean arterial pressure during exercise and why?

Answer 21

mean arterial pressure increases due to the heart pumping harder

Question 22

what does increasing the mean arterial pressure do to the pressure difference between vessels?

Answer 22

increases it

Question 23

how is blood directed during exercise?

Answer 23

changing the resistance of different vessels

Question 24

what are examples of different vessles?

Answer 24

• aorta
• arteries
• arterioles
• capillaries
• venules
• veins

Question 25

what are the 3 different kinds of arteries?

Answer 25

* elastic * muscular * resistance

Question 26

what kind of artery is the aorta?

Answer 26

elastic artery

Question 27

what kind of artery are arteries?

Answer 27

muscular arteries

Question 28

what kind or artery are arterioles?

Answer 28

resistance vessels

Question 29

what are the characteristics of elastic arteries?

Answer 29

* wide lumen * elastic wall * damp pressure variations

Question 30

what are characteristics of muscular arteries?

Answer 30

* wide lumen * strong non-elastic wall * low resistance conduit

Question 31

what are characteristics of resistance vessels?

Answer 31

* narrow lumen * thick contractile wall * control resistance and therefore flow * allow regional redirection of blood

Question 32

what kind of vessels are capillaries?

Answer 32

exchange vessels

Question 33

what are characteristics of exchange vessels?

Answer 33

* narrow lumen * thin wall

Question 34

what kind of vessels are venules and veins?

Answer 34

capacitance vessels

Question 35

what are characteristics of capacitance vessels?

Answer 35

* wide lumen * distensible wall * low resistance conduit * acts as reservoir * allows fractional distribution of blood between veins and the rest of circulation

Question 36

what does a vessels characteristics relate to?

Answer 36

its function

Question 37

what do thick walls allow?

Answer 37

greater pressure to be contained

Question 38

what do elastic walls allow?

Answer 38

* to absorb more energy to stop blood pressure going too high once the heart beats * to release energy preventing it from going too low once the heart is relaxed

Question 39

how thick are the walls of the capillaries?

Answer 39

1 cell thick to allow diffusion to occur

Question 40

what does capillaries having a narrow lumen mean for their surface area to volume ratio?

Answer 40

high surface area to volume ratio

Question 41

what percentage of blood is in the veins and venules at any one time?

Answer 41

2/3

Question 42

What is A?

Answer 42

Pulmonary vein

Question 43

What is B?

Answer 43

Superior vena cava

Question 44

What is C?

Answer 44

Inteatrial septum

Question 45

What is D?

Answer 45

Right atrium

Question 46

What is E?

Answer 46

Right AV valve

Question 47

What is F?

Answer 47

Inferior vena cava

Question 48

What is G?

Answer 48

Right ventricle

Question 49

What is H?

Answer 49

Pulmonary and aortic valves

Question 50

What is I?

Answer 50

Interventricular septum

Question 51

What is J?

Answer 51

Left AV valve

Question 52

What is K?

Answer 52

Left ventricle

Question 53

What is L?

Answer 53

Pulmonary trunk

Question 54

What is M?

Answer 54

pulmonary vein

Question 55

What is N?

Answer 55

left atrium

Question 56

What is O?

Answer 56

pulmonary artery

Question 57

what is the myocardium?

Answer 57

muscular tissue of the heart

Question 58

what is the atrium?

Answer 58

where blood returns to

Question 59

what does the septum do?

Answer 59

separates the 2 halves of the heart

Question 60

what is the ventricle?

Answer 60

chamber that ejects blood out of the heart

Question 61

where does the aorta carry blood from and to?

Answer 61

from the heart to systemic circulation

Question 62

what does the vena cava do?

Answer 62

returns blood to the heart from systemic circulation

Question 63

where does the pulmonary trunk carry blood from and to?

Answer 63

from the heart to the lungs

Question 64

where do the pulmonary veins carry blood from and to?

Answer 64

from the lungs to the heart

Question 65

what are the chordae tendinae?

Answer 65

thin chords that attach to AV valves to prevent them from turning inside out

Question 66

what are papillary muscle?

Answer 66

attached to chordae tendinae to maintain tension and support preventing the valves from turning inside out once the heart contracts

Question 67

how many pumps are in the heart?

Answer 67

2

Question 68

which wall of the heart is the thickest?

Answer 68

left ventricle due to pumping blood to the whole body, whereas the right is just to the lungs

Question 69

what do valves in the heart do?

Answer 69

prevent backflow of blood

Question 70

what are the 2 kinds of valves?

Answer 70

semi-lunar valves (SL) atrioventricular valves (AV)

Question 71

what are the two semi-lunar (SL) valves?

Answer 71

aortic valve pulmonary valve

Question 72

what are the two atrio-ventricular (AV) valves?

Answer 72

mitral valve tricuspid valve