Cardiovascular System Part 2 W5

Question 1

What makes up the heart wall?

Answer 1

Epicardium
Myocardium
Endocardium

Question 2

What is myocardial infraction?

Answer 2

Blockage in coronary blood flow results in cell damage

Exercise training protects against heart damage during an myocardial infraction

Question 3

What is the epicardium?

Answer 3

Serves as lubricative outer covering

Question 4

What the myocardium?

Answer 4

Provides muscular contractions that eject blood from the heart chambers

Question 5

What is the endocardium?

Answer 5

Serves as protective inner lining of the chambers and valves

Question 6

What are the differences between heart muscle and skeletal muscle?

Answer 6

Heart:
- 1 nuclei
- Has cellular junctions (intercalated discs)
- Involuntary neural control
- No regeneration potential (no satellite cells)

Skeletal:
- Multiple nuclei
- No junctional complexes
- Voluntary neural control
- Some regeneration potential (via satellite cells

Question 7

What does contraction of the heart depend on?

Answer 7

Electrical stimulation of the myocardium

Question 8

What is the SA node?

Answer 8

Pacemaker initiating depolarization

Question 9

What ae bundle branches?

Answer 9

Connect atria to left and right ventricle

Question 10

What is the AV node?

Answer 10

Passes depolarisation to the ventricles

Question 11

What are purkinje fibres?

Answer 11

Spread wave or depolarization throughout ventricles

Question 12

What is the P wave (ECG)?

Answer 12

Atrial depolarisation

Question 13

What is the QRS complex (ECG)?

Answer 13

Ventricular depolarization and atrial repolarization

Question 14

What is the T wave (ECG)?

Answer 14

Ventricular repolarisation

Question 15

What happens to intraventricular pressure as ventricles contract?

Answer 15

It rises

Question 16

What does S-T segment depression suggest?

Answer 16

Myocardial ischemia

Question 17

What is athleroscelrosis

Answer 17

Fatty plaque that narrows coronary arteries

Question 18

What is myocardial ischemia?

Answer 18

Recues blood flow to myocardium

Question 19

How much of total oxygen consumption does the maintenance of basal metabolism compromise?

Answer 19

10-20%

Question 19

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

Answer 19

Improves the heart’s antioxidant capacity
Improves function of ATP-sensitive potassium channels

Question 20

What does increased oxygen delivery rely on?

Answer 20

Increased coronary blood flow

Question 21

What does chronotropic mean?

Answer 21

Heart rate increases

Question 22

What does inotropic mean?

Answer 22

Contractility increases

Question 23

What is the main metabolic vasodilator during coronary circulation?

Answer 23

Adenosine

Question 24

What type of control is on coronary blood vessels?

Answer 24

Metabolic

Question 25

What happens to coronary flow during rest?

Answer 25

80% takes place during diastole because of vessel compression during systole

Question 26

What happens to coronary flow during heavy exercise?

Answer 26

40-50% occurs during systole due to less time in the diastole

Question 27

What is the tricuspid valve?

Answer 27

Situated between the right ventricle and right atrium of the heart

Most inferior and largest valve

Question 28

How does the heart create an action potential?

Answer 28

By itself
It does not need parasympathetic or sympathetic activity