Week 6 - Cardiovascular Physiology

Question 1

What is the basic function of the CV system?

Answer 1

Delivery of O2
Removal of waste products 
Support thermoregulation and control body fluid balance
Hormone transport
Regulation of immune function

Question 2

Name the system parts and functions

Answer 2

Heart - pressure creation
Arteries and arterioles - carry blood away from heart
Capillaries - exchange of gases
Veins and venules - carry blood towards the heart

Question 3

What happens to the right side of the heart throughout a complete cycle?

Answer 3

Receives blood returning from throughout the body

Pumps deoxygenated blood to the lungs

Question 4

What happens to the left side of the heart throughout a complete cycle?

Answer 4

Receives oxygenated blood from the lungs

Pumps oxygenated blood to all other tissues in the body

Question 5

What type of valves are bicuspid and tricuspid?

Answer 5

Atrioventricular valves

Question 6

What is the function of semilunar valves?

Answer 6

Stops pumped blood returning back into the ventricle

Question 7

What are the two types of semilunar valves?

Answer 7

Pulmonary (right side)

Aortic (left side)

Question 8

On an ECG, what does the P wave represent?

Answer 8

Atrial, depolarisation

Question 9

On an ECG, what does the QRS comples represent?

Answer 9

Ventricular depolarisation (masks atrial repolarisation)

Question 10

On an ECG, what does the T wave represent?

Answer 10

Ventricular repolarisation

Question 11

What is Henry’s Law?

Answer 11

When a mixture of gas is in contact with liquid each gas dissolves in the liquid in proportion to its partial pressure and solubility until equilibrium is achieved and the gas partial pressure are equal in both locations.

Question 12

What pressure gradient do gases diffuse to?

Answer 12

From high to low areas of pressure

Question 13

What is systolic blood pressure the measure of?

Answer 13

The pressure exerted by blood on vessel walls during ventricular systole (contraction phase)

Question 14

What is diastolic blood pressure the measure of?

Answer 14

The pressure exerted by blood on vessel walls during ventricular diastole (relaxation phase)

Question 15

How is mean arterial pressure calculated?

Answer 15

2/3 DBP + 1/3 SBP

Question 16

What is cardiac volume and how is it calculated?

Answer 16

Total volume of blood pumped by the ventricle per minute
Q(L) = HR x SV
Q(L) = HR x (ESV - EDV)

Question 17

What is stroke volume and how is it calculated?

Answer 17

Total blood pumped out of the left ventricle per beat

SV = ESV - EDV

Question 18

What does EDV and ESV stand for and mean?

Answer 18

EDV - end diastolic volume, at the end of the relaxtion phase how much blood is there
ESV - end systolic volume, at the end of the contraction phase how much blood is there

Question 19

How is heart rate variability measured using ECG?

Answer 19

Assessing R-R variability, (the R from the QRS complex)

Question 20

What type of control is sympathetic and parasympathetic?

Answer 20

Autonomic control

Question 21

What does the sympathetic system do to the CV system?

Answer 21

Increase HR 
Increase inotropism (contractions)

Question 22

What does the parasympathetic system do to the CV system?

Answer 22

Decrease HR 
Decrease inotropism (contractions)

Question 23

Regarding HR variability, what is a sign of a healthier heart?

Answer 23

More variability, shows our body can quickly respond to stimulus.

Question 24

What has higher HR variability been associated with?

Answer 24

Good emotional regulation
Well being
Information processing

Question 25

What has lower HR variability been associated with?

Answer 25

Depression, anxiety, poor emotional regulation IBS Aging Cardiac mortality

Question 26

What is VO2 and how is it calculated?

Answer 26

The difference between volume of gas inhaled and volume of gas exhaled per unit of time = [(V1 x F1O2) - (V2 x F2O2)]/T

Question 27

What are the determinants of VO2?

Answer 27

Blood flow and oxygen extraction

Question 28

What is maximal oxygen uptake?

Answer 28

The integrated functioning of the pulmonary, cardiovascular and muscle systems to uptake, transport and utilise O2

Question 29

Who two athletes had the same VO2max but differing lactate thresholds, who would perform better in an endurance event?

Answer 29

The athlete with the lower lactate threshold

Question 30

What happens to BP during exercise and why?

Answer 30

Increases due to increase in Q thus more blood flows harder and faster

Question 31

What happens to Q during exercise and why?

Answer 31

Q increases HR increases SV increases

Question 32

What happens to O2 extraction during exercise and why?

Answer 32

Increased extraction of O2 from the blood | Because affinity to Hb decreases

Question 33

What conditions lead to a decrease of O2s affinity to Hb?

Answer 33

Increase in acidity Increase in PCO2 Increase in temp Increase in 2-3 BPG

Question 34

What is 'A-VO2 difference'?

Answer 34

The difference in oxygen saturation of the blood going to the tissues (in the arteries) and of the blood returning to the heart (in the veins).

Question 35

How are rates of oxygen utilisation increased?

Answer 35

Increased extraction of O2 from the blood Dilation of peripheral vascular beds (increased gas exchange) Increased Q Increase in pulmonary blood flow (lungs) Increased ventilation