Unit Two: The Heart

Question 1

What are the two main layers of the pericardium?

Answer 1

1. Fibrous pericardium. 2. Serous pericardium.

Question 2

What are the 2 layers of the serous pericardium?

Answer 2

1. Visceral (epi)pericardium. 2. Parietal pericardium.

Question 3

Where is the visceral pericardium located?

Answer 3

On the surface of the heart.

Question 4

What is the fibrous pericardium? What is it composed of?

Answer 4

The tough outer sac. Dense network of collagen fibers.

Question 5

What is the serous pericardium?

Answer 5

The two layered lining of the pericardium.

Question 6

What is the pericardial cavity?

Answer 6

The space between the parietal pericardium and the epicardium (visceral pericardium) that covers the outer surface of the heart.

Question 7

What are the three layers of the wall of the heart? (from superficial to deep)

Answer 7

1. Epicardium. 2. Myocardium. 3. Endocardium.

Question 8

What is the function of the fibrous pericardium?

Answer 8

To stabilize the position of the heart.

Question 9

What are the two layers of the epicardium?

Answer 9

1. A mesothelium. 2. An underlying, supporting layer of areolar tissue.

Question 10

What is the myocardium?

Answer 10

Cardiac muscle tissue that forms the atria and ventricles. It is the thickest layer.

Question 11

What is the function of the endocardium?

Answer 11

It covers the inner surfaces of the heart, including those of the heart valves.

Question 12

What is of clinical significance about the endocardium?

Answer 12

This simple squamous epithelium is continuous with the endothelium of the attached great vessels.

Question 13

Which has thicker walls atria or ventricles?

Answer 13

Ventricles.

Question 14

Which ventricle has thicker walls?

Answer 14

The left ventricle.

Question 15

What do the right and left coronary arteries supply?

Answer 15

The heart wall muscles with oxygen and nutrients.

Question 16

What are the two branches of the right coronary artery?

Answer 16

1. Right marginal. 2. Posterior interventricular.

Question 17

What does the right marginal artery supply?

Answer 17

The right border of the heart.

Question 18

What does the posterior interventricular artery supply?

Answer 18

The posterior surface of the left and right ventricle.

Question 19

What do the coronary arteries branch off of?

Answer 19

The ascending aorta.

Question 20

What are the two branches of the left coronary arteries?

Answer 20

1. Anterior inter-ventricular. 2. Circumflex.

Question 21

What does the anterior interventricular artery supply?

Answer 21

The anterior surface of both ventricles and most of the inter-ventricular septum.

Question 22

What does the circumflex artery supply?

Answer 22

The left atrium and ventricle.

Question 23

Where do the coronary veins bring deoxygenated blood?

Answer 23

The right atrium.

Question 24

What does the great cardiac vein run alongside?

Answer 24

The anterior interventricular artery.

Question 25

What does the middle cardiac vein run alongside?

Answer 25

The posterior interventricular artery.

Question 26

What does the small cardiac vein run alongside?

Answer 26

The marginal artery.

Question 27

Where do all the cardiac veins drain into?

Answer 27

The coronary sinus.

Question 28

Where is the coronary sinus located?

Answer 28

In the posterior part of the coronary sulcus.

Question 29

Where do the right and left coronary arteries travel within?

Answer 29

The coronary sulcus.

Question 30

What node generated impulses?

Answer 30

Sinoatrial node (pacemaker).

Question 31

Where do impulses generated in the heart pause?

Answer 31

The atrioventricular node.

Question 32

What bundle connects the atria to the ventricles?

Answer 32

The atrioventricle bundle.

Question 33

What stimulates the contractile cells in both ventricles?

Answer 33

Subendocardial conducting network (Purkinje fibers).

Question 34

A blockage in which coronary vessel would result in a disruption of the conduction system of the heart?

Answer 34

The anterior interventricular.

Question 35

What happens during systole?

Answer 35

Chambers contract.

Question 36

What happens during diastole?

Answer 36

Chambers filling/relaxing.

Question 37

What happens during atrial systole?

Answer 37

Atrial contraction forces a small amount of blood into the relaxed ventricles.

Question 38

What valves are open during atrial systole?

Answer 38

The atrioventricular (AV) valves (Tricuspid and mitral valve).

Question 39

What valves are open during ventricular systole?

Answer 39

The semi-lunar valves (aortic and pulmonary valves).

Question 40

What is blood pressure?

Answer 40

The force of the blood pushing against the inside walls of blood vessels.

Question 41

What is the systole blood pressure?

Answer 41

Pressure of blood on artery walls while ventricles are contracting.

Question 42

What is the diastolic blood pressure?

Answer 42

Pressure of blood on artery walls while the ventricles are not contracting.

Question 43

What creates the "lub" sound?

Answer 43

The AV valves closing.

Question 44

What creates the "dub" sound?

Answer 44

The semi-lunar valves closing.

Question 45

What are the chordae tendineae?

Answer 45

Connective tissue fibers where the free edges of the cusps attach.

Question 46

What are papillary muscles?

Answer 46

Where the fibers of the chodae tendineae arise. They are muscular projections of the inner surface of the right ventricle

Question 47

What is the function of the chordae tendineae?

Answer 47

They limit the movement of the cusps when the valve closes. This prevents backflow of blood from the right ventricle into the right atrium.

Question 48

What are the trabeculae carneae?

Answer 48

A series of irregular muscular ridges inside the internal surface of the right ventricle.

Question 49

Where are pectinate muscles found?

Answer 49

They extend along the inner surface of the right auricle and across the anterior wall of the right atrium.

Question 50

What structures allow a bypass of pulmonary circulation before lungs are needed?

Answer 50

Foramen/Fossa ovalis and ductus arteriosus.

Question 51

What is cardiomegaly?

Answer 51

An abnormal enlargement of the heart.

Question 52

What is a pericardial effusion?

Answer 52

When there is fluid within the pericardial cavity, causing less blood to be able to be taken in.

Question 53

What is constrictive pericarditis?

Answer 53

A thickening/fibrosis of the parietal pericardium.