Cardiovascular System

Question 1

What is the function of the cardiovascular system?

Answer 1

To maintain homeostasis of ISF

Question 2

What is the function of the heart?

Answer 2

To generate movement

Question 3

What is the function of the vasculature?

Answer 3

To create a pathway for the blood

Question 4

What is hematocrit?

Answer 4

The % of blood that is RBCs

Question 5

What is flow rate?

Answer 5

The AMOUNT of blood that travels through the vessel at a given time.

Question 6

What makes blood flow?

Answer 6

The pressure gradient

Question 7

What is velocity of flow?

Answer 7

The DISTANCE traveled through the vessel during a given time.

Question 8

Which vessel has the highest pressure?

Answer 8

Aorta

Question 9

Which vessel has the lowest pressure?

Answer 9

Vena cava

Question 10

Which vessels have the most change in pressure?

Answer 10

Arterioles

Question 11

What influences the rate of flow the most?

Answer 11

Radius of the vessel

Question 12

What is the membranous sac encasing the heart?

Answer 12

Pericardium

Question 13

What lubricates the heart so it does not stick when it contracts?

Answer 13

Pericardial fluid

Question 14

What is the pacemaker of the heart?

Answer 14

SA Node

Question 15

Explain the funny current.

Answer 15

The influx of Na+ when reaching the threshold of HYPERpolarization.

Question 16

Refractory period of the heart means?

Answer 16

Another heart beat cannot be stimulated.

Question 17

What is contractility?

Answer 17

Strength of contraction

Question 18

____ from postganglionic neurons and _____ from adrenal medulla bind to ___ receptors on cardiac myocytes.

Answer 18

Norepinephrine, epinephrine, beta1-adrenergic

Question 19

During diastole the heart is contracted or relaxed?

Answer 19

Relaxed

Question 20

During diastole are the AV and SL valves open or shut?

Answer 20

AV: open / SL: shut

Question 21

During systole are the AV and SL valves open or shut?

Answer 21

AV: shut / SL: open

Question 22

Which valves are closing during the 1st heart sound?

Answer 22

Atrial-ventricular valves (AV)

Question 23

Which valves are closing during the 2nd heart sound?

Answer 23

Semilunar valves (SL)

Question 24

What is the electrical conduction pathway?

Answer 24

• SA node
• AV node
• Bundle of His
• Bundle branches
• Purkinje Fibres

Question 25

What does an ECG measure?

Answer 25

The electrical changes of the whole heart during a heartbeat

Question 26

What does an action potential measure?

Answer 26

The electrical changes of one myocardium cell

Question 27

What repolarizes the heart?

Answer 27

K+

Question 28

What does the P wave stand for (ECG)?

Answer 28

Atrium depolarization

Question 29

What does the QRS wave stand fro (ECG)?

Answer 29

Ventricular depolarization

Question 30

What does the T wave stand for?

Answer 30

Ventricular repolarization

Question 31

Why do you not see atrium repolarization on an ECG?

Answer 31

Because the ventricular depolarization is so strong, it overtakes the ECG's readings.

Question 32

What is active hyperemia?

Answer 32

Increase in flow because of high demand - When there is less O2, more CO2 eg. exercising

Question 33

What is reactive hyperemia?

Answer 33

The increase of blood flow following an occlusion (ischemia) | eg. leg falling asleep

Question 34

What is myogenic autoregulation?

Answer 34

Constricting/dilating of the vessels due to stretch, | - Stretch-activated channels in the SM of arterioles causes these channels to intake Ca2+ to constrict again.

Question 35

What are 3 examples of local control in the cardiovascular system?

Answer 35

- active hyperemia - reactive hyperemia - myogenic autoregulation

Question 36

What is the AV node?

Answer 36

- controls the heart rate | - slowing the electrical signal from the SA node

Question 37

What is the SA node?

Answer 37

- group of cells on the right atrium - pacemaker - generates actin potentials

Question 38

At what point is the heart most full of blood?

Answer 38

End of diastole

Question 39

What does end-diastolic volume mean?

Answer 39

The volume of blood in the heart at the end of diastole. (full of blood)

Question 40

What does end-systolic volume mean?

Answer 40

The volume of blood in the heart at the end of ejection (systole).

Question 41

What is stroke volume?

Answer 41

The amount of blood that is ejected from the left ventricle

Question 42

Which vessel has the smallest diameter and thinnest walls?

Answer 42

Capillaries

Question 43

What are the three types of capillaries?

Answer 43

- continuous - fenestrated - sinusoid

Question 44

Does blood move slowly or quickly through capillaries?

Answer 44

The slowest rate.

Question 45

What is bulk flow?

Answer 45

mass movement of fluid between blood and ISF

Question 46

What is the most compliant vessel?

Answer 46

Veins

Question 47

Resistance, diameter of veins?

Answer 47

Low resistance, large diameter

Question 48

What kind of muscle do veins use? Sympathetic or parasympathetic vasoconstriction?

Answer 48

Smooth muscle, sympathetic

Question 49

Where does most exchange take place?

Answer 49

Capilleries

Question 50

What are the 2 Starling forces?

Answer 50

- hydrostatic pressure | - osmotic pressure

Question 51

For a sympathetic contraction epinephrine and norepinephrine bind to what kind of receptors on the myocyte cells?

Answer 51

Beta1-adrenergic receptors

Question 52

Is the relaxed heart in diastole or systole? The contracted heart?

Answer 52

Relaxed - diastole | Contracted - systole

Question 53

During isovolumetric contraction what part of the heart is filled with blood?

Answer 53

The ventricles

Question 54

During vigorous exercise where does most of the blood fro the heart go to?

Answer 54

The muscles

Question 55

What is the function of the barorecptors?

Answer 55

To maintain homeostasis of blood pressure

Question 56

Where are the two locations of baroreceptors?

Answer 56

Aortic arch and carotid arteries

Question 57

What is the heartbeat initiated by?

Answer 57

The conducting system of the heart | - all of its nodes control itself, heart can keep beating after you die

Question 58

Depolarization during the action potential of a pacemaker cell in the SA node is due to an

Answer 58

influx of Ca2+

Question 59

What is hemostasis?

Answer 59

Blood clotting

Question 60

What is hematopoiesis?

Answer 60

Blood cell production

Question 61

How are RBCs destroyed? And after roughly how many days?

Answer 61

~ 120 days | by spleen

Question 62

What is anemia?

Answer 62

Decreased ability to carry O2 in blood

Question 63

Where do platelets come from?

Answer 63

The are fragments of MEGAKARYOCYTES in the bone marrow

Question 64

What converts fibrinogen to fibrin?

Answer 64

thrombin