cardiovascular system design

Question 1

what are the 5 main functions of the cardiovascular system?

Answer 1

1. contractions of individual cardiac cells must occur at regular intervals and be synchronized
2. valves must fully open
3. valves must not leak
4. muscle contractions must be forceful
5. ventricles must fill adequately durning diastole

Question 2

about how many liters are there in the interstitial compartment (internal environment)?

Answer 2

12 L

Question 3

about how many liters are there in the intracellular compartment?

Answer 3

30 L

Question 4

about how many liters are there in the circulating plasma compartment?

Answer 4

3 L

Question 5

out of the kidney, skeletal muscle, liver/GI tract, brain and heart which organ has the highest VO2 (O2 consumption as a percentage)

Answer 5

skeletal muscle (about 27%)

Question 6

out of the kidney, skeletal muscle, liver/GI tract, brain, skin and heart which organ has the lowest VO2 (O2 consumption as a percentage)

Answer 6

kidney (about 7%)

Question 7

at any point in time, what percentage of blood is systemic circulation?

Answer 7

~84%

remainder in hear (~7%) and pulmonary vessels (~9%)

Question 8

where does the right ventricle pump blood into?

Answer 8

pulmonary circulation

Question 9

how does re-oxygenated blood return to the L. atrium

Answer 9

pulmonary veins

Question 10

what two valves regulate the entry of blood into systemic circulation?

Answer 10

mitral and aortic valves

Question 11

what two valves regulate the entry of blood into pulmonary circulation?

Answer 11

tricuspid and pulmonary valves

Question 12

define cardiac output

Answer 12

quantity of blood per unit time pumped into the aorta by the heart
SV x HR

Question 13

what is the typical cardiac output for a resting individual?

Answer 13

5 L/min

Question 14

what are the 3 major determinants of stroke volume?

Answer 14

• ventricular preload
• ventricular afterload
• myocardial contractility

Question 15

list 3 factors that can decrease CO

Answer 15

• siting or standing from lying position
• rapid arrhythmia
• heart disease

Question 16

list 5 factors that can increase CO

Answer 16

• anxiety and excitement
• eating
• exercise
• high environmental temp
• pregnancy
• epi

Question 17

what does starling’s law state

Answer 17

stroke volume increases as end diastole volume increases (other things being constant)

Question 18

define mean arterial pressure

Answer 18

the average pressure over the entire cardiac cycle. It is estimated from diastolic pressure and pulse pressure
MAP= CO x TPR

Question 19

define pulse pressure

Answer 19

it is the difference between the systolic and diastolic pressure

Question 20

define systolic pressure

Answer 20

peak pressure reached during blood ejection from the heart

Question 21

define diastolic pressure

Answer 21

lowest pressure point during which the heart is filling with blood

Question 22

what is the dichrotic notch

Answer 22

it is the small dip caused by the backfilling of the aortic valve as it closes

Question 23

where is the circulatory system is blood pressure the lowest? the highest?

Answer 23

the lowest: pulmonary veins

highest: large arteries

Question 24

is taking BP via the ausculatory method considered direct or indirect?

Answer 24

indirect

Question 25

how do you measure pulmonary venous and left arterial pressures?

Answer 25

need to use pulmonary capillary wedge pressure

Question 26

what is the average pulse pressure in a resting adult?

Answer 26

40 mmHG

Question 27

give two equations to calculate pulse pressure

Answer 27

``` PP= SD-DP PP= SV/compliance ```

Question 28

in the short term, how is MAP controlled? how is this accomplished?

Answer 28

by altering peripheral resistance and cardiac output | this is accomplished neurally and hormonally

Question 29

how is long term control of MAP achieved?

Answer 29

primarily by altering blood volume via the kidneys

Question 30

what is the units for human blood pressure?

Answer 30

mercury (because we calculate BP in regards the environmental pressure)