the cardiovascular system 2

Question 1

the part of the heart that causes it

blood pressure is generated by?

Answer 1

ventricular contraction

Question 2

formula for pulse pressure

Answer 2

Systolic pressure- Diastolic pressure

Question 3

in terms of vavles, aorta, arteries , ventricles…

describe what happens in ventricular contraction

Answer 3

ventricles contract
semi-lunar valves open
aorta and arteries expand and store pressure in the elastic walls

Question 4

describe what happens in ventricular relaxation

Answer 4

ventricles relax
semi-lunar valves shut
elastic recoil of arteries sends blood forward to the rest of the circulatory system

Question 5

factors that affect blood pressure

Answer 5

Cardiac Output
Peripheral Vascular resistance
Volume

Question 6

involves pulse and diastolic pressure

formula for the mean arterial pressure(MAP)

Answer 6

Diastolic + 1/3 Pulse Pressure

Question 7

involves heart rate and stroke volume

formula for cardiac output

Answer 7

Stroke Volume x Heart Rate

Question 8

involves Cardiac output and peripheral vascular resistance

formula for MAP

Answer 8

CO (Cardiac Output) x PVR (Peripheral Vascular Resistance)

Question 9

the PVR is aka

Answer 9

systemic vascular resistance

Question 10

involves EDV and ESV

formula for stroke volume

Answer 10

EDV-ESV

Question 11

factors that affect the HR

Answer 11

autonomic innervation
hormones
fitness levels
age

Question 12

factors that affect stroke volume

Answer 12

heart size
fitness levels
gender
contractility
duration of contraction
preload(EDV)
afterload(resistance)

Question 13

factors that affect CO

Answer 13

HR and SV

Question 14

preload

Answer 14

the initial stretching or tension of the cardiac muscle fibers in the ventricles just before they contract

Question 15

afterload

Answer 15

the pressure against which theheart must work to eject blood during systole

Question 16

factors that affect blood vessel resistance

Answer 16

vessel diameter
vessel length
blood viscosity

Question 17

viscosity

Answer 17

The viscosity of a fluid is a measure of its resistance to deformation at a given rate

Question 18

how does a decrease in radius affect blood vessel resistance

Answer 18

if the radius decreases be one half, the resistance decreases by 16 fold(2^4). so simply, a small change in radius results to a high change in resistance of the blood vessel

Question 19

Hypervolaemia

Answer 19

increased blood volume

Question 20

Hypovolaemia

Answer 20

decreased blood volume

Question 21

factors affecting blood volume

Answer 21

Oedema = accumulation fluid in interstitial space

Disruption in fluid exchange between blood and tissues

Hormonal Regulation

Kidney Function

Question 22

think about how blood volume affects cardiac output and therefore BP

how does blood volume affect blood pressure

Answer 22

Increase in Blood Volume:

If blood volume increases, there is more blood circulating in the vascular system.
The increased volume leads to an increase in cardiac output, the amount of blood pumped by the heart per minute.
An increase in cardiac output results in an increase in blood pressure.

Decrease in Blood Volume:

If blood volume decreases, there is less blood in circulation.
The decreased volume leads to a decrease in cardiac output.
A decrease in cardiac output results in a decrease in blood pressure

Question 23

factors affecting osmotic balance in the blood

Answer 23

Increased hydrostatic pressure – eg heart failure – back pressure2. Decreased plasma protein concentration – osmotic balance disrupted
Increase in interstitial proteins

Question 23

involves contraction and dilation

vascular tone

Answer 23

balance between contraction and dilatation in a vessel

Question 24

contraction and dilation of a blood vessel depends on?

Answer 24

Composition of the vessels
Local factors like N.O and Endothelin
Mechanical factors like stretch
Metabolic factors like CO2 and O2 availability
Temperature