Week 5- Cardiac structure and function

Question 1

Where does the right atrium receive blood from?

Answer 1

The inferior and superior vena cava

Question 2

What side of the heart would you find the tricuspid valve?

Answer 2

right

Question 3

What is the role of the epicardium?

Answer 3

serve as a lubricant outer coating

Question 4

What does the myocardium provide?

Answer 4

muscular contractions that eject blood from the heart chambers

Question 5

What does the endocardium serve as?

Answer 5

protective inner lining of the chambers and valves

Question 6

Where does the heart receive its blood supply from?

Answer 6

coronary arteries

Question 7

What is myocardial infarction (MI)?

Answer 7

-blockage of the coronary blood flow results in cell damage

Question 8

What is the role of the sinoatrial node?

Answer 8

pacemaker that initiates depolarisation

Question 9

What is the role of the atrioventricular node?

Answer 9

-passes depolarisation to ventricles

Question 10

Why does the AV node allow for a brief delay in the depolarisation of the ventricles?

Answer 10

To allow for ventricle filling

Question 11

What is the role of the bundle branches?

Answer 11

connect atria to the left and right ventricle

Question 12

What is the role of the purkinje fibres?

Answer 12

spread the wave of depolarisation throughout the ventricles

Question 13

Where do action potentials originate in the heart?

Answer 13

SA node

Question 14

Once the action potential travels from the SA to the AV where is it passed to?

Answer 14

interventricular septum

Question 15

What does the action potential travel along to reach the apex of each ventricle?

Answer 15

bundle branches

Question 16

Where does the the purkinje fibres carry the action potential to and from?

Answer 16

from the bundle branches to the ventricular walls

Question 17

What is the P wave showing in an ECG?

Answer 17

arterial depolarisation (SA and AV)

Question 18

What does the QRS complex show in an ECG?

Answer 18

Ventricular depolarisation and arterial repolarisation

Question 19

What is the T wave showing in an ECG?

Answer 19

Ventricular repolarisation

Question 20

What is atherosclerosis?

Answer 20

Fatty plaque that narrows coronary arteries reducing blood flow to myocardium

Question 21

What is myocardial ischemia?

Answer 21

reduced blood flow to the myocardium

Question 22

How does exercise reduce the amount of myocardial damage from a heart attack?

Answer 22

-improves the hearts antioxidant capacity
-improves the function of ATP-sensitive potassium channels

Question 23

What effect does the parasympathetic nervous system have on the regulation of heart rate?

Answer 23

-slows the heart rate by inhibiting the SA and AV node via the vagus nerve

Question 24

What effect does the sympathetic nervous system have on the regulation of heart rate?

Answer 24

-increases heart rate by stimulating the SA and AV node via cardiac accelerator nerves

Question 25

What causes an increase in myocardial oxygen consumption?

Answer 25

-increase in coronary blood flow with only modest contributions of increase in haematocrit and oxygen extraction

Question 26

What is chronotropic?

Answer 26

increase in heart rate

Question 27

What is inotropic?

Answer 27

increased contractility

Question 28

What is the main metabolic vasodilator?

Answer 28

adenosine

Question 29

At what point in heart contraction does most coronary flow take place?

Answer 29

80% during diastole due to vessel compression during systole