Cardiac Anatomy and Physiology

Question 1

The cardiovascular system function is impacted by all of the following, EXCEPT:
a. Endocrine
b. Immune
c. Nervous
d. Urinary

Answer 1

b. Immune

Question 2

Blood is composed of formed elements including:

Answer 2

• Cells/cell fragments
• Erythrocytes
• Leukocytes
• Platelets
• Plasma

Question 3

Hematocrit

Answer 3

% of blood volume that is erythrocytes

Question 4

Major function(s) of erythrocytes:

Answer 4

gas transport

Question 5

Platelets

Answer 5

colorless, non-nucleated cell fragments with numerous granules produced when cytoplasmic portions of large bone marrow cells pinch off and enter circulation

Question 6

Platelets play a major role in

Answer 6

Blood clotting

Question 7

Pulmonary Circulation

Answer 7

Oxygen-poor blood from right ventricle travels to the lungs and then returns oxygen-rich blood to the left atrium

Question 8

Systemic Circulation

Answer 8

Oxygen-rich blood from the left ventricle travels to all the organs and tissues of the body, except the lungs, and returns oxygen-poor blood to the right atrium.

Question 9

Arteries carry blood

Answer 9

away from the heart

Question 10

Veins carry blood

Answer 10

toward the heart

Question 11

Pulmonary arteries carry _______ blood to the lungs

Answer 11

deoxygenated

Question 12

Pulmonary veins carry _______ blood to the heart

Answer 12

oxygenated

Question 13

Distribution of the blood is based on

Answer 13

physiologic demand

Question 14

Force exerted by the blood

Answer 14

Pressure

Question 15

volume of blood moved per unit time

Answer 15

Flow

Question 16

Define resistance

Answer 16

how difficult it is for blood to flow between two points at any given pressure difference.

Question 17

Factors affecting resistance

Answer 17

• Blood viscosity
• Total blood vessel length
• Blood vessel radius

Question 18

Epicardium

Answer 18

most superficial layer of heart tissue; fibrous layer

Question 19

Myocardium

Answer 19

middle layer of heart, cardiac muscle

Question 20

Endocardium

Answer 20

Inner layer of heart continuous with lining of blood vessels entering and leaving the heart.

Question 21

Describe the contraction of the heart

Answer 21

Squeezing (like a a fluid-filled balloon)

Question 22

Why are gap junctions important?

Answer 22

They allow the impulse spread of cardiac electrical activity

Question 23

What neurotransmitter and branch of the autonomic nervous system binds to Beta-adrenergic receptors?

Answer 23

Norepinephrine and epinephrine/sympathetic

Question 24

What neurotransmitter and branch of the autonomic nervous system binds to muscarinic receptors?

Answer 24

acetylocholine/parasympathetic

Question 25

Coronary arteries exit where to supply the heart?

Answer 25

Behind the aortic valve cusps in the aortic root

Question 26

Where do the coronary veins drain?

Answer 26

Coronary Sinus > Right Atrium

Question 27

Sinoatrial node

Answer 27

pacemaker for the heart

Question 28

What allows both the R and L atria to contract at relatively the same time?

Answer 28

Gap junctions allow for fast transmission of depolarization

Question 29

Describe the excitation of the heart.

Answer 29

**SA node** > internodal pathways > **AV Node** > Interventricular septum > bundle of His > Right and Left Bundle Branches > Purkinje Fibers

Question 30

Pacemaker Potential

Answer 30

slow, gradual depolarization (SA node)

Question 31

Automaticity

Answer 31

capacity for spontanous, rhythmic self-excitation

Question 32

Excitation-Contraction Coupling

Answer 32

the series of events that link the action potential (excitation) of the muscle cell membrane (the sarcolemma) to muscular contraction

Question 33

Why is the refractory period important in cardiac muscle?

Answer 33

prevents fatigue

Question 34

Systole

Answer 34

ventricular contration (blood ejection)

Question 35

Diastole

Answer 35

ventricular relaxation, blood filling

Question 36

Isovolumetric ventricular contraction

Answer 36

ventricles contracting but blood cannot leave since all valves are closed, cardiac muscle is developing tension.

Question 37

Ventricular Ejection

Answer 37

period of ventricular contraction, in which muscle fibers shorten, blood is forced out of ventricles into the aorta and pulmonary trunk

Question 38

What opens the aortic and pulmonary valves?

Answer 38

Rising pressure in ventricles form contraction

Question 39

Stroke Volume

Answer 39

volume of blood ejected from each ventricle during systole | SV = EDV - ESV

Question 40

Isovolumetric ventricular relaxation

Answer 40

- first part of diastole, ventricles begin to relax - aortic and pulmonary values close - No blood is entering or leaving

Question 41

Ventricular Filling

Answer 41

- AV valves open, blood flows from atria to ventricles

Question 42

80% of ventricular filling occurs ____ before atrial contraction, the final 20% occurs during the _______

Answer 42

passively, atrial kick

Question 43

Cardiac Output

Answer 43

Volume of blood pumped out of each ventricle per unti time (L/min) | CO = HR x SV ## Footnote Normal CO ~ 5L/min

Question 44

Parasympathetic neuron stimulation of the SA node cuases

Answer 44

HR to decrease

Question 45

Sympathetic innervation of the SA node causes

Answer 45

HR to increase

Question 46

Chronotropic Effects

Answer 46

Changes to the heart **rate**

Question 47

Preload

Answer 47

changes in end-diastolic volume

Question 48

Afterload

Answer 48

aterial pressure against whcih the ventricles pump

Question 49

Frank-Starling Mechanism

Answer 49

ventricle contracts more forecefully when it has been filled to a greater degree.

Question 50

How does venous return affect cardiac output/stroke volume?

Answer 50

Increases them

Question 51

Inotropic

Answer 51

Contractility

Question 52

Norepinephrine binds to:

Answer 52

beta-adrenergic receptors

Question 53

Ejection Fraction

Answer 53

SV/EDV (%) - Quantifies contractility

Question 54

How does increased afterload affect the ejection fraction?

Answer 54

reduces SV, therefore EF