Unit 3 - The Heart

Question 1

Pulmonary Circuit

Answer 1

Right side of the heart

Carries blood from lungs > heart > lungs

Gas exchange

Question 2

Systemic Circuit

Answer 2

Left side of the heart

Carries blood from heart > tissues > heart

Transports oxygenated blood

Question 3

Base (of the heart)

Answer 3

Wide upper (superior) portion of the heart where large vessels attach

Question 4

Apex (of the heart)

Answer 4

Narrow, pointed (tip), inferior portion of the heart

Question 5

Pericardium

Answer 5

Double-walled sac that encloses the heart

Parietal layer (outer layer): two smaller layers, one of fibrous connective tissue and a thin serous layer

Visceral layer (inner layer): made of serous membrane

Question 6

Pericardial Cavity

Answer 6

Space between the layers of the pericardium that contians pericardial fluid

Question 7

Epicardium

Answer 7

The visceral pericardium

The outermost layer of the three layers (epicardium, myocardium, and endocardium)

Question 8

Myocardium

Answer 8

Muscle of the heart

Thickest layer

The second layer of the three layers (epicardium, myocardium, and endocardium)

Question 9

Endocardium

Answer 9

Lines the inner surfaces of the heart

The third (innermost) layer of the three layers (epicardium, myocardium, and endocardium)

Question 10

Right Atria

Answer 10

Right superior chamber

Receives blood returning to the heart

Question 11

Left Atria

Answer 11

Left superior chamber

Receives blood returning to the heart

Question 12

Right Ventricle

Answer 12

Right inferior chamber

Pumps blood into arteries and away from the heart

Question 13

Left Ventricle

Answer 13

Left inferior chamber

Pumps blood into arteries and away from the heart

Question 14

Interatrial Septum

Answer 14

Muscle wall that separates the atria

Question 15

Interventricular Septum

Answer 15

Muscle wall that separates the ventricles

Question 16

Tricuspid Valve (Right AV Valve)

Answer 16

Controls flow between the right atria and ventricle

Three cusps

Question 17

Mitral (Bicuspid) Valve (Left AV Valve)

Answer 17

Controls flow between the left atria and ventricle

Two cusps

Question 18

Chordae Tendinae

Answer 18

Cords that connect the AV valves to papillary muscles on the floor of the ventricles

Question 19

Semilunar Valves

Answer 19

Controls flow into great arteries

2 semilunar valves: pulmonary valve and aortic valve

Question 20

Pulmonary Semilunar Valve

Answer 20

Opening between right ventricle and pulmonary trunk

Question 21

Aortic Semilunar Valve

Answer 21

Opening between left ventricle and aorta

Question 22

Blood Flow Circuit

Answer 22

1. Superior and inferior venae cavae
2. Right atrium
3. Right ventricle
4. Pulmonary valve
5. Pulmonary trunk
6. Right and left lungs
7. Pulmonary veins
8. Left atrium
9. Left ventricle
10. Aortic valve
11. Ascending aorta
12. Body organs

Question 23

Cardiomyocytes

Answer 23

Cardiac muscle cells

Myogenic pacemaker

Autorhythmic

Striated

Short, thick, branched cells

Contacts several others to form a network

Joined by intercalated discs

Contains desmosomes and gap junctions

Looks like varying levels of pink striated blocks separated by thin discs with intermittent purple nuclei

Question 24

Cardiac Conduction System

Answer 24

1. SA node
2. Atrial myocardium
3. AV node
4. AV bundle
5. Purkinje fibres
6. Ventricular myocardium

Question 25

Atrioventricular (coronary) sulcus

Answer 25

Separates atria and ventricles

Question 26

Interventricular Sulci (2)

Answer 26

Overlies interventricular septum that divides right ventricle from left Contain coronary arteries

Question 27

Coronary Circulation

Answer 27

Blood flow to the heart itself

Question 28

Left Arterial Supply

Answer 28

Consists of: left coronary artery, anterior interventricular branch, and circumflex branch

Question 29

Left Coronary Artery

Answer 29

Branches off the ascending aorta Supplies blood to the left atrium, both ventricles, 2/3 of the anterior interventricular septum, and the posterior left ventricle

Question 30

Anterior Interventricular Branch

Answer 30

Supplies blood to both ventricles and 2/3 of the anterior interventricular septum

Question 31

Circumflex Branch

Answer 31

Supplies left atrium Supplies posterior left ventricle Passes around left side of heart in coronary sulcus Gives off left marginal branch Ends on the posterior side of the heart

Question 32

Right Arterial Supply

Answer 32

Consists of: right coronary artery, right marginal branch, and posterior interventricular branch Supplies blood to right atrium, SA node, right ventricle, and the posterior walls of ventricles

Question 33

Right coronary artery

Answer 33

Braches off ascending aorta Supplies right atrium and SA node

Question 34

Right Marginal Branch

Answer 34

Supplies lateral aspect of the right atrium and ventricle

Question 35

Posterior Interventricular Branch

Answer 35

Supplies posterior walls of ventricles

Question 36

Heart Venous Drainage

Answer 36

Coronary blood returns to right atrium by way of the coronary sinus Coronary sinus has three inputs: great cardiac vein, posterior interventricular, and left marginal vein

Question 37

Purkinje Fibers

Answer 37

Receive conductive signals and activate the ventricles by stimulating the ventricular myocardium