Ch. 20 The Heart

Question 1

What system is the heart, blood, and blood vessels part of?

Answer 1

The cardiovascular system

Question 2

What is the function of the cardiovascular system?

Answer 2

• To distribute oxygen and nutrients to the cells of the body
• To take away carbon dioxide and other wastes

Question 3

How many beats does the heart do per day?

Answer 3

100,000

Question 4

How many liters of blood does the heart pump daily?

Answer 4

8,000

Question 5

Beginning with the right atrium, what is the order of the valves through which blood will pass?

Answer 5

Blood will pass through the tricuspid valve (right AV valve), the pulmonary valve, the mitral valve (left AV valve), and finally the aortic valve.

Question 6

Which division of the autonomic nervous system would increase heart rate?

Answer 6

The sympathetic nervous system would increase heart rate. The cardioacceleratory center controls sympathetic neurons that increase heart rate.

Question 7

Oxygen-poor blood is pumped to ______ within the ______ circuit

Answer 7

The lungs

Pulmonary circuit

Question 8

Oxygen-rich blood is pumped to ______ within the ______ circuit

Answer 8

The body

Systemic circuit

Question 9

What is the pathway the pulmonary circuit takes?

Answer 9

Oxygen-poor blood from the right ventricle through the pulmonary arteries, to the lungs. Oxygen-rich blood back through the pulmonary veins to the left atrium

Question 10

What is the pathway the systemic circuit takes?

Answer 10

Oxygen-rich blood from the left ventricle through the systemic arteries. Oxygen-poor blood through systemic veins back to the right atrium

Question 11

Blood returning to the heart from the systemic circuit must complete the…?

Answer 11

Pulmonary circuit before reentering the systemic circuit

Question 12

Which circuit does the left side of the heart supply blood to?

Answer 12

The systemic circuit

Question 13

Which circuit does the right side of the heart supply blood to?

Answer 13

Pulmonary circuit

Question 14

____ carry blood away from the heart

Answer 14

Arteries

Question 15

____ return blood to the heart

Answer 15

Veins

Question 16

What are great vessels?

Answer 16

The largest veins and arteries in the body; connected to the heart

Question 17

What do capillaries do?

Answer 17

Interconnect the smallest arteries and the smallest veins

Question 18

Why are capillaries called exchange vessels?

Answer 18

Their thin walls permit the exchange of nutrients, dissolved gases, and wastes between the blood and surrounding tissue

Question 19

What are the 4 muscular chambers of the heart?

Answer 19

Right atrium
Right ventricle
Left atrium
Left ventricle

Question 20

What does the right atrium do?

Answer 20

Receives blood from the systemic circuit and passes it to the right ventricle

Question 21

What does the right ventricle do?

Answer 21

Pumps blood into the pulmonary circuit

Question 22

What does the left atrium do?

Answer 22

Collects blood from the pulmonary circuit and empties it into the left ventricle

Question 23

What does the left ventricle do?

Answer 23

Pumps blood into the systemic circuit

Question 24

When the heart beats, what contracts first?

Answer 24

The atria

Question 25

Where is the heart located?

Answer 25

In the thoracic cavity near the anterior chest wall, directly posterior to the sternum

Question 26

Where are the great vessels (veins and arteries) connected?

Answer 26

To the superior end of the heart at its base

Question 27

What is the name of the pointed tip of the heart?

Answer 27

Apex

Question 28

What does heart size depend on?

Answer 28

Age, height, weight, sex

Question 29

What are the walls of the heart, from deep to superficial?

Answer 29

Endocardium Myocardium Pericardium

Question 30

Define endocardium

Answer 30

Inner layer whose simple squamous epithelium is continuous with the endothelial lining of blood vessels

Question 31

Define myocardium

Answer 31

Spiral bundles of cardiac muscle cells

Question 32

Define pericardium

Answer 32

Surrounds the heart and consists of an outer fibrous pericardium and an inner serous pericardium

Question 33

What is the name of the expandable extension of an atrium?

Answer 33

Auricle

Question 34

What is the coronary sulcus?

Answer 34

A deep groove that marks the border between the atria and the ventricles

Question 35

What marks the boundary between the left and right ventricles?

Answer 35

The anterior interventricular sulcus and the posterior interventricular sulcus

Question 36

What lies in the coronary and interventricular sulci?

Answer 36

Fat

Question 37

What are the heart wall's distinct layers, from superficial to deep?

Answer 37

Outer epicardium Middle myocardium Inner endocardium

Question 38

What does the outer epicardium cover?

Answer 38

The surface of the heart

Question 39

What does the middle myocardium contain?

Answer 39

Cardiac muscle cells, connective tissues, blood vessels, and nerves

Question 40

What does the inner endocardium cover?

Answer 40

The inner surfaces of the heart, including the heart valves

Question 41

What does the connective tissues of the heart include?

Answer 41

Large numbers of collagen and elastic fibers

Question 42

Each cardiac muscle cell is wrapped in...?

Answer 42

A strong elastic sheath

Question 43

What are the atria separated by?

Answer 43

The interatrial septum

Question 44

What are the two atrioventricular valves?

Answer 44

Tricuspid valve | Mitral valve

Question 45

What do the atrioventricular valves permit?

Answer 45

Blood to flow only in only one direction: from the atria to the ventricles

Question 46

What are the two semilunar valves?

Answer 46

Pulmonary valve | Aortic valve

Question 47

What are the two great veins the right atrium receives blood from the systemic circuit through?

Answer 47

Superior vena cava and the inferior vena cava

Question 48

Where does the superior vena cava deliver blood to the right atrium from?

Answer 48

From the head, neck, upper limbs, and chest

Question 49

Where does the inferior vena cava deliver blood to the right atrium from?

Answer 49

The rest of the trunk, viscera, and lower limbs

Question 50

What does the foramen ovale become?

Answer 50

The fossa ovalis

Question 51

What are cusps?

Answer 51

Blood travels from the right atrium into the right ventricle through a broad opening bordered by three fibrous flaps, called cusps

Question 52

What do contractions on the papillary muscles pull on?

Answer 52

The chordae tendineae

Question 53

What are trabeculae carneae?

Answer 53

Muscular ridges on the internal surface of the right ventricle

Question 54

Which valve guards the entrance to the left ventricle?

Answer 54

The mitral valve

Question 55

Where does the mitral valve permit blood to flow from and into?

Answer 55

From the left atrium into the left ventricle

Question 56

What is the difference between the internal organization of the left and right ventricles?

Answer 56

The left ventricle does not have a moderator band

Question 57

Blood leaves the left ventricle through the _____ and enters the _____

Answer 57

Aortic valve | Ascending aorta

Question 58

What is the function of the atria?

Answer 58

To collect blood that is returning to the heart and to convey it to the ventricles

Question 59

Which ventricle is larger and why?

Answer 59

The left ventricle is much larger than the right ventricle because the left ventricle has thicker walls that enable it to push blood through the body’s systemic circuit. The right ventricle needs to pump blood at lower pressure to and from the lungs

Question 60

When the ventricles are _____, the tricuspid and mitral valves are _____ and the aortic and pulmonary valves are _____

Answer 60

Relaxed Open Closed

Question 61

When the ventricles are _____, the tricuspid and mitral valves are _____ and the aortic and pulmonary valves are _____

Answer 61

Contracting Closed Open

Question 62

Which valve is the most common to falter?

Answer 62

The mitral valve

Question 63

When using a stethoscope, what are faulty valves heard as?

Answer 63

Heart murmurs

Question 64

What prevents the backflow of blood from the ventricles to the atria when the ventricles are contracting?

Answer 64

The atrioventricular (AV) valves

Question 65

What prevents the backflow of blood from the pulmonary trunk and aorta into the right and left ventricles?

Answer 65

The pulmonary and aortic semilunar valves