Heart 2

Front 1

The heart is enclosed in a double-walled sac called the:
a duodenum
b.dynamic duo
c. pericardium

Back 1

c. pericardium

Front 2

name and describe the outer wall of the pericardium

Back 2

name: parietal pericardium.
Descrip:
Outside: tough and fibrous layer of dense irregular connective tissue
Inside: thin, serous layer which turns inward at the base

Front 3

How is the visceral pericaridium is formed?

Back 3

It is formed by the inner, serous layer of the pericardium turning inward on itself.

Front 4

The ________________ (aka the _________ _____________)covers the heart surface.

Back 4

epicardium (visceral pericardium)

Hint 4

Epi's Vespa ran over her heart.

Front 5

Between the parietal and visceral membranes is a space called the ______________ _____________

Back 5

Pericardial cavity

Front 6

The pericardial cavity contains ___ to ___ ml of pericardial fluid

Back 6

5 to 30 ml

Front 7

What purpose(s) does the pericardial fluid serve?

Back 7

It lubricates the membranes and allows the haert to beat almost without friction.

Front 8

Name the three layers the heart wall is composed of

Back 8

1. epicardium (surface - simple squamous epithelium)
2. Endocardium (inner chamber lining - simple squamous endothelium)
3. Myocardium - thickest layer - performs the work of the heart.

Front 9

The heart has a meshwork of collagenous and elastic fibers that make up the FIBROUS SKELETON. Name 4 funcitons of the fibrous skeleton.

Back 9

1. structural support
2. anchors myocytes giving them something to pull against.
3. electrical insulation
4. MAY aid in refilling the heart with blood.

Hint 9

Electrical S (structural) And M (anchors myocytes) may refill the heart with blood.

Front 10

How many chambers does the heart have?

Back 10

four

Front 11

The two superior chambers are the:

Back 11

Right and left Atria

Front 12

The two chambers at the base of the heart are the:

Back 12

Right and left atria (remember that the "base" of the heart is located superioraly)

Front 13

The two inferior heart chambers are the:

Back 13

Right and left ventricles

Hint 13

Think "V" points downward forming an apex like the inferior portion of the heart and "Ventrical" starts with "V".

Front 14

The right and left atria are ______ walled ________ ing chambers for blood ______ ing to the heart via the great veins

Back 14

Thin walled receiving chambers for blood returning to the heart...

Front 15

The right and left VENTRICALS are the _________s that ________ blood into the ___________s and keep it flowing around the body

Back 15

They are the pumps that eject blood into the arteries and keep it ....

Front 16

On hte posterior side of the heart each atrium has a small earlike extension called a(n) _________ that slightly increases its volume

Back 16

auricle.

Front 17

The ___________ (aka _____) sulcus encricles the heart near the base and separates the atria above from the ventricles below.

Back 17

coronary (aka atrioventricular) sulcus

Front 18

The sulci extending obliquely down the front of the heart from the coronary sulcus is called the

Back 18

anterior interventricular sulcus.

Front 19

The _________ __________ _______ divides the right ventricle from the left.

Back 19

internal interventricular septum.

Front 20

The right and left atrium are separated by a wall called the ______ _______

Back 20

interatrial septum

Front 21

The right atrium and both auricles exhitit internal ridges of myocardium called _______ _________ .

Back 21

Pectinate muscles.

Front 22

T or F. The walls of the left ventricle are two to four times as thick as the other chambers of the heart

Back 22

True. this is because the left ventricle has the greatest workload - pumping blood through the entire body.

Front 23

Both ventricles exhibit internal ridges called:
a. bivalve divisors
b. trabeculae carneae
c. mitral insurgents

Back 23

b. trabeculae carneae

Front 24

Between each atrium and its ventricle there is a:
a. valve
b. schnooter
c. interventroatriator

Back 24

a. valve

Front 25

True / False
There are 4 valves where the great veins empty into the atria.

Back 25

FALSE. There are NO valves where the great veins empty into the atria.

Front 26

T/F There is a valve at the exit from each ventricle into its great artery.

Back 26

TRUE.

Front 27

T/F the atrioventricular (AV) valves regulate the openings where the great veins empty into each atria

Back 27

FALSE. THERE ARE NO VALVES where the great veins empty into the atria. The AV valves regulate the openings between the atria and ventricles.

Front 28

The right AV valve has ______ cusps and the left AV valve has ______.

Back 28

The right has 3 and is called the tricuspid valve and the left has 2 and is called the bicuspid valve.

Front 29

The left AV valve is aka the:
a. fish valve
b. Pope's valve
c. Mitral valve.

Back 29

c. mitral valve

Front 30

Stringlike ______ _______ connect the valve cusps to conical _______ _______ on the floor of the ventricles.

Back 30

stringlike tendenous cords connect the valve to conical papillary muscles on the floor of the ventricle.

Front 31

Each valve consists of 2 or 3 fibrous flaps of tissue called:
a. cardioflappers
b. cusps or leaflets
c. tissue windows

Back 31

b. cusps or leaflets

Front 32

The semilunar valves are aka

Back 32

the pulmonary and aortic valves

Front 33

what do the semilunar valves do?

Back 33

the regulate the flow of blood from the ventricles into the great arteries.

Front 34

Each of the semilunar valves has _____ cusps
a. 4
b. 3
c. no

Back 34

b. each semilunar valve has three cusps.

Front 35

T/F there are tendinous cords on the semilunar valves.

Back 35

False. There are NO tendinous cords on the semilunar valves.

Front 36

When the ventricles are relaxed and their pressure is low the AV valves:
a. are tightly closed
b. are open
c. pressure has no effect on the AV valves

Back 36

b. when ventricles are relaxed, their cusps hand down limply and both AV valves are open.

Front 37

T/F The papillary muscles on the floor of the ventricles cause the AV valves to close

Back 37

FALSE. They prevent them from gulging excessively into the atria or turning inside out like a windblown umbrella

Front 38

When pressure rises in the contracting ventricles, it forces the pulmonary and aortic valves to close so blood is not lost

Back 38

FALSE. Contracting ventricals force the pulmonaruy and aortic valves to open so blood can be ejected from the heart.

Front 39

_____ _______ is any failure of a valve to prevent reflux. It frequently results from _______ _______

Back 39

valular insufficiency.
Rheumatic Fever

Front 40

An insufficiency in which one or both mitral valve cusps bulge into the atrium during ventricular contraction is called:

Back 40

Mitral valve prolapse (MVP)

Front 41

The blood vessels of the heart wall which supply the myocardium constitute the _____ ________.

Back 41

coronary circulation.

Front 42

About ______ % of the circulating blood goes to meet the metabolic needs of the haert.

Back 42

5

Front 43

The right atrium and sinoatrial node (pacemaker) are supplied with blood by the:

Back 43

right coronary artery. (RCA)

Front 44

A heart attack is also known as a(n) _________ ________

Back 44

Myocardial Infarction

Front 45

a point where two arteries come together and combine their blood flow to points fatther downstreatm are called:

Back 45

anastomoses

Front 46

____________ is a ssense of heaviness or pain in the chest resulting from temporary and reversible ischemia or deficiency of blood flow to the cardiac muscle

Back 46

Angina

Front 47

_________________ ________ is the sudden death of a patch of myocardium resulting from long-term obstruction of the coronary circulation.

Back 47

Myocardial infarction

Front 48

T/F the coronary arteries receive MORE arterial blood when the ventricles contract than when they relax

Back 48

FALSE. The coronary arteries receive LESS arterial blood when the ventricles contract than when they relax.

Front 49

T/F In the coronary blood vessels, diastolic blood flow is greater than systolic blood flow

Back 49

True.

Front 50

Afer flowing through capillaries of theheart wall, about 20% of the coronary blood empties directly from multiple, small ________ veins into the ________ atrium and ventricle

Back 50

thesbian veins,
right atrium

Front 51

80% of coronary blood returns to the right atrium by...

Back 51

the coronary sinus (it collects blood from the great cardiac vein, the posterior interventricular vein, the left marginal vein and other smaller veins.)

Front 52

The sympathetic pathway to the heart originates with neurons in the...

Back 52

lower cervical to upper thoracic spinal cord

Front 53

Cardiac nerves arise from the cervical ganglis (fig 15.4) and lead mainly to the ...

Back 53

ventricular myocardium

Front 54

Sympathetic fibers t tje cprpmaru arteries ________ and _________ coronary blood flow during exercise.
dilate/constrict / increase / decrease

Back 54

dilate them an dincrease coronary blood flow during exercise

Front 55

THE parasympathic pathway to the heart is through the _____ ________s

Back 55

vagus nerves

Front 56

The RIGHT vagus nerve innervates mainly the _________________
______ ___________
___________

Back 56

electrical centre of the heart called the SA node.

Front 57

The LEFT vagus nerve innervates mainly the centre called the ______ _______

Back 57

AV NODE

Front 58

The vagus nerves __________ the heartbeat.
Slow / Increase

Back 58

Slow

Front 59

The steady background firing of the vagus nerves called _______ _________ normally holds the resting heartrate down to about ____ to ___ bpm.

Back 59

Vagal Tone normally holds the resting heart rate down to about 70 to 80 bpm

Front 60

T/F The sympathetic and parasympathetic nerves to the heart are what makes it beat.

Back 60

FALSE. The heart beat is set off by the heart's own internal pacemaker, but these nerves can MODIFY it.

Front 61

T/F Cardiac myocytes are said to be ANTIRHYTHMIC because they cannot depolarize without a dentropic flange

Back 61

FALSE. Cardiac myocytes are said to be AUTO-RHYTHMIC bc they DEPOLARIZE SPONTANEOUSLY at regular time intervals !

Front 62

Myocytes that lose the ability to contract and become specialized for generating action potentials constitute the ______ _______ system.

Back 62

cardiac conduction.

Front 63

The cardic conduction system controls _________________ ______________
_______________
_______________

Back 63

it controls the route and tiing of electrical conduction to ensure that the four chambers are coordinated with each other.

Front 64

In what order do electrical signals arise and travel through the cardiac conduction system? (Purkinje fibers, AV node, SA node, AV bundle)

Back 64

1. SA NODE (the pacemaker - initiates heart beat, determines heart rate
2. AV node (gateway to the ventricles
3. AV bundle (pathway by which signals leave the AV node.
4. Purkinje fibers. (distribute electrical excitation to the myocytes of the ventricles.

Front 65

The function of the sinoatrial (SA) node is:

Back 65

pacemaker that initiates each heartbeat and determine the heart rate

Front 66

The function of the atrioventricular (AV) node is:

Back 66

Electrical gateway to the ventricles.

Front 67

The funciton of the atrioventricular (AV) bundle is.

Back 67

it's the pathway via which signals leave the AV node.

Front 68

The function of the Purkinje Fibers is

Back 68

distribute the electrical excitation to the myocytes of the ventricles.

Front 69

The Purkinje fibers form a more elaborate network in the _________ ventrical than in the _______

Back 69

more elaborate network in the LEFT ventrical than in the right.

Front 70

The ______ _______ acts as an insulator to prevent currents from gettin go the ventricles by any other route.

Back 70

fibrous skeleton.

Front 71

T/F CARDIAC MYOCYTES (heart muscle cells) are able to pass electrical signals from cell to cell

Back 71

TRUE. This is something skeletal muscle cannot do.

Front 72

A MYOCYTE is notched at the ends and typically linked to two or more neighbouring myocytes by the mechanical and electrical junctions of the __________ ____________

Back 72

intercalated discs (yes, that is spelt correctly)

Front 73

The T-TUBULES in cardiocytes are much larger than in skeletal muscle. During excitation of the cell, the admit supplemental ____ _____ from the extracellular fluid to activate muscle contraction.

Back 73

Calcium IONS

Front 74

Myocytes are joined end to end by thick connections called ____ ______s

Back 74

Intercalated discs.

Front 75

Name three distinctive features of intercalated disks NOT found in skeletal muscle

Back 75

1. interdigitating folds.
2. Mechanical junctions.(fascia adherens and desmosomes)
3. Electrical (gap) junctions

Front 76

The broad band in which the actin of the thin myofilaments is anchored to the plasma membrane and via transmembrane proteins one cell is linked to the next it called:

Back 76

the fascia adherens (pg 730)

Front 77

the mechanical junctions between cells that interrupt the facia adherens here and there and allow myocytes to pull on each other w/o pulling apart are the

Back 77

desmosomes.

Front 78

Channels which allow ions from one cell to the next and are responsible for the ability of the atria and ventricles to contract in unison are called

Back 78

Electrical or GAP junctions.

Front 79

Cardiac muscle relies almost entirely on __________ respiration to make ATP

Back 79

aerobic

Front 80

Mitochondria take up about _____ % of a a typical myocyte.

Back 80

25% (as opposed to about 2% in skeletal muscle fibers)

Front 81

At rest, the heart gets about ____ % of its energy from fatty acids, ___ % from glucose and ____ from other fuels such as ketones,lactic acid and amino acids.

Back 81

60% fatty acids
35% glucose
5% ketones, lactic acid and amino acids.

Front 82

Cardiac muscle is more vulnerable to _______ deficiency than it is to the lack of any specific fuel

Back 82

OXYGEN.

Front 83

The heart muscle is not prone to fatigue because....

Back 83

it make little use of anaerobic fermentation or the oxygen debt mechanism.

Front 84

Contraction in the heart is called _______ and relaxation is called ______

Back 84

Systole / Distole

Front 85

The normal heartbeat, triggered by the SA node is called:

Back 85

SINUS RHYTHM

Front 86

any region of spontaneous firing other than the SA node is called:

Back 86

ectopic focus.

Front 87

THE AV NODE produces a slower heartbeat of 40 to 50 bpm called a

Back 87

NODAL RHYTHM

Front 88

abnormal cardiac rhythm is called

Back 88

ARRHYTHMIA

Front 89

The failure of any part of the cardiac donduction system to transmit signals is called

Back 89

HEART BLOCK

Front 90

Insufficient blood flow to a tissue is called:

Back 90

Ischemia

Front 91

When ectopic foci in the atria set off extra contractions and the atria beat 200 to 400 times per minute this is called

Back 91

Atrial Flutter

Front 92

A serious arrhythmia caused by electrical signals arriving at different regions of the mycardium at widely different times is called ___ ____. It causes the heart to look like a "Bag of worms"

Back 92

ventricular fibrillation

Front 93

the cessation of cardiac output with the ventricals either mothionless or in fibrillation is called

Back 93

Cardiac Arrest

Front 94

FIBRILLATION IS

Back 94

the rapid, irregular, and unsynchronized contraction of the muscle fibers of the heart.

Front 95

There are two major classes of fibrillation, what are they?

Back 95

atrial fibrillation and ventricular fibrillation.
ATRIAL fibrillation can be a chronic condition, usually treated with anticoagulation and sometimes with conversion to normal sinus rhythm.
VENTRICULAR fibrillation is rapidly fatal if not reversed by defibrillation.

Front 96

T/F the cells of the SA node do NOT have a stalbe resting membrane potential

Back 96

TRUE. Their membrane potential starts at about - 60 mV and drifts upward showing a gradual depolarization called the PACEMAKER POTENTIAL.

Front 97

The PACEMAKER POTENTIAL is the result of

Back 97

a slow inflow of Na+ withought a compensating outflow of K+

Front 98

When the pacemaker potential reaches a threshold of _______ mV, voltage regulated ____ _____ _____ open and Ca2+ flows in from the ECF

Back 98

-40mV
fast calcium channels

Front 99

Each polarization of the SA node sets of ______ heartbeat(s)
a. 1
b. 2
c. 16

Back 99

a. 1

Front 100

The fastest signals in the conduction system travel through the __ ___ and the ___ ___ at a speed of ______ / second

Back 100

AV BUNDLES and the Purkinje fibers at a speed of 4 metres per second.

Front 101

Signals reach the ____ _____s before the rest of the myocardium

Back 101

papillary muscles. They contract and take up slack in the tendinous cords

Front 102

VEntricular systole begins at the __________ of the heart.
a. apex
b. nexus
c. base

Back 102

a. apex

Front 103

T/F CARDIAC MYOCYTES have a stable resting potential of -90mV and normally depolarize only when stimulated.

Back 103

TRUE (unlike the cells of the SA node.)

Front 104

The Sarcoplasmic Reticulum provides _____ % to _____ % of the Ca2+ needed for myocardial contraction

Back 104

90 to 98%

Front 105

What is an absolute refractory period. How long is it in cardiac muscle?

Back 105

in physiology, is a period of time during which an organ or cell is incapable of repeating a particular action, or (more precisely) the amount of time it takes for an excitable membrane to be ready for a second stimulus once it returns to its resting state following an excitation. 250 msec.

Front 106

A composite recording of all the action potentials produced by the nodal and myocardial cells is called:

Back 106

an ECG (or EKG)

Front 107

When a signal from the SA node spreads through the atria and depolarizes them, a ____ ______ is produced on the ECG

Back 107

P Wave.

Front 108

The time required for impulses to trael from the SA node to the AV node is shown by the __ __ ____ of the ECG

Back 108

PQ Segment.

Front 109

The _____ is produced when the signal from the AV node spreads through the ventricular myocardium

Back 109

QRS complex

Front 110

Ventricular systole begins in the

Back 110

ST segment

Front 111

The ST segment corresponds to

Back 111

the plateau in the mocardial action potential. It respresents the time during whcih the ventricles contract and eject blood.

Front 112

The ______ is generated by bentricular repolarization immediately before diastole

Back 112

T wave

Front 113

The T Wave is generated by ___ ____ immediately before ____

Back 113

ventricular repolarization immediately before diastole.

Front 114

T/F the ventricles take longer to DEpolarize than they do to REpolarize.

Back 114

TRUE. This is why the T Wave is smaller and more spread out than the QRS complex.

Front 115

The T wave can be recognized by its relatively _____ peak.
a. Sharp
b. needle-nosed
c. rounded

Back 115

c. rounded.

Front 116

Listening to sounds made by the body is called

Back 116

auscultation

Front 117

The "lubb-dubb" sound is created by the ___
a. s1 and s2
b. T4 and T6
c. Lubb and Dubb

Back 117

a. s1 and s2

Front 118

S1 and S2 occur in conjunction with the _____ of the valves as a result of ________

Back 118

closing of the valves as a result of turbulence in the bloodstream and movements of theheart wall.

Front 119

Name the four phases of the cardiac cycle

Back 119

a. ventricular filling
b. isovolumetric contraction
c. ventricular ejection
d. iosvolumetric relaxation.

Front 120

The Right ventrical
a. ejects twice the volume of the left ventrical
b. half the volume of the left ventrical
c. they both eject the same amount of blood

Back 120

c. To maintain homeostasis, the two ventricles MUST have EQUAL output.