The Heart Flashcards Preview

A&P 203 > The Heart > Flashcards

Flashcards in The Heart Deck (265):
0

Which cavity is the heart found

The thoracic cavity

1

Where is the heart found

Between 2nd and 5th intercostal space

2

If midsagittal cut is made...

2/3 of the heart lies left of the midline

3

Anatomical axis

Angle(vector) of how the heart is orientated in the thoracic cavity

46degrees from midsagittal cut

4

Structure (a-c)

A. Superior base of heart
B. Apex
C. Size

5

Superior base of heart

Site of great vessel attachment

6

Apex

Hangs relatively free

Immediately above diaphragm

7

Size

Size of adult fist

300g

8

Pericardium

Heart enclosed by (protected by) double walled connective tissue sac

9

Pericardial sac

-sac around the heart

- pericardial fluid inside of sac
Decreases friction on the heart while beating

10

Parietal pericardium

Outer component

Touches chest or thoracic cavity

11

Visceral pericardium

Epicardium

Inner component

Touches surface of the heart

Squamous epithelium plus some adipose tissue

12

Pericardial cavity

Containing pericardial fluid

(Reduces friction when heart contracts)

13

Heart wall (1-3)

1. Epicardium
2. Myocardium
3. Endocardium

14

Myocardium

Cardiac muscle (musculature of the heart)

15

Vast majority of weight of heart

Myocardium

16

Myocardium conducts

Excitation

17

Myocardium color due to

1. Blood
2. myoglobin (an iron and oxygen binding protein)

18

Endocardium
1. Location
2. Type of tissue

1. Inner aspect

2. Squamous epithelium but no adipose tissue

19

Endocarditis

Inflammation of the endocardium

May be due to bacterial infection, viral infection, etc.

20

Which is in contact with blood

Endocardium

21

Cardiovascular system

1. Heart
2. blood vessels

22

Circulatory system

Heart
Blood vessels
Blood

23

Left side of the heart

Fully oxygenated blood arrives from lungs via pulmonary veins

Blood sent to all organs of body via aorta

24

Aorta

Sends blood to all organs of the body

25

Right side of the heart

Lesser oxygenated blood arrives from inferior and superior venae cavae

26

Blood sent to the lungs via

Pulmonary trunk

Right side

27

Venae cavae

Lesser oxygenated blood arrives from inferior and superior venae cavae

28

Heart is located in ____

Mediastinum

Between the lungs

29

Base

Wide portion of heart

Blood vessels attached here

30

Apex

Inferior end

Tilts to the left

Tapers to point

31

_____ wide at base

3.5 inches

32

_____ in from base to apex

5 inches

33

______ inches anterior to posterior

2.5 inches

34

Weighs

10 ounces

35

Pericardium

Double walled sac (pericardial sac) that encloses the heart

Allows heart to beat without friction
Provides room to expand, yet resists excessive expansion

Anchored to diaphragm inferiorly

Sternum anteriorly

36

Parietal pericardium
--Where
--Two layers

Outer wall of sac

Superficial fibrous layer of connective tissue

Deep. Thin. Serous layer

37

Pericardium

Double walled sac (pericardial sac)
Encloses the heart

38

Layers of the pericardium

1. Parietal

2. Visceral ( epicardium)

39

Pericardial cavity

Space inside the pericardial sac filled with 5-30mL of pericardial fluid

40

The myocardium is _______ in the _____ than _____

The ventricles than the atria or auricles

41

Myocardium ____ with similarities to _____

Cardiac muscle cells with similarities to smooth muscle and striated muscle

42

Myocardium ~~ myosin

Contracts spontaneously

43

Oxygen-rich blood is located in the

Right side chambers

44

Arteries carry blood -- from the heart

Away

45

Veins carry blood -- the heart

Towards

46

Which wave corresponds to atrial repolarization

P wave

47

Chordae tendineae conducts the cups of the AV valve to papillary muscles of the ventricles

False

48

The right and left coronary arteries containing oxygen rich blood originates from the base of the aorta

True

49

The -- of the conduction system is known as the pacemaker

SA node

50

The --- is the inferior end of the heart that is bluntly pointed

Apex

51

The --- lines the heart chambers

Fibrous pericardium

52

Pericarditis

Inflammation of the membranes

Painful friction rub with each heartbeat

53

the dupp sound occurs when the semilunar valves are closing during ventricular distole

TRUE

54

lumine

hole in the middle of the heart

55

endocardium surrounds the ____

lumine

56

there is ___ on the epicardium

FAT (white)
adipose tissue on surface

57

the pericardium

allows the heart to beat without friction, provides room to expand, yet resists excessive expansion

58

the pericardium is ___

anchored to the diaphragm - inferiority

sternum - anteriorly

59

Dark cardiac muscle

myocardium

60

the myocardium layer of...

cardiac muscles proportion to work load

61

the myocardium muscle...

spirals around heart
which
produces wringing motion

62

the myocardium is the...

1. fibrous skeleton of the heart
2. framework of collagenous and elastic fibers

63

the myocardium provides..

1.structural support
2. attachment for cardiac muscle
3. anchor for valve tissue

64

myocardium -- between ----- and ----

electrical insulation between atria and ventricles

*important in timing and coordination of contactile activity*

65

the four chambers of the heart __

keep pressure down when going through the lungs

66

right and left atria

1. two superior chambers
2. receive blood returning to heart
3. Auricles (seen on surface) enlarge chambers

67

Auricles

enlarge chambers

68

right and left ventricles

1. Two inferior chambers
2. Pump blood into arteries

69

semilunar valve

1.control flow into great arteries
2. Open and close because of blood flow and pressure

70

pulmonary semilunar valve

in opening between right ventricle and pulmonary trunk

71

aortic semilunar valve

opening between left verticle and aorta

72

valves ensure

one way flow of blood through the heart

73

AV valve or

atrioventricular valve

74

atrioventricular valves (AV)

control blood flow between atria and ventricles

75

RIght AV valve has

three cusps
*TRICUSPID valve*

76

Left AV valve has

two cusps
Mitral
Bicuspid valve

77

chordae tendineae

cord connects AV valves to papillary muscle on floor of ventricles

78

the chordae tendineae...

prevents AV valve from flipping inside out
or
bulging into the atria when the ventricles contract

79

semilunar valves keep

blood pressure up

80

Coronary arteries (ventral side) location

1.come directly off of aorta just above the aortic SL valve

81

Coronary arteries (ventral side) purpose

blood supply to the myocardium

82

_____ plaque that can block the coronary arteries

atherosclerosis plaques

-heart by-pass surgery (as many as 7 by-passes)

83

Coronary sinus location

dorsal side

84

coronary sinus (2)

1. expanded, venous type vessel
2. drains blood from heart into the right atrium

85

coronary sinus is

the only place in body that when it contracts no blood
when it relaxes gets blood

86

blood flow to the heart muscle during ____ is ___

ventricular contraction
slowed
(unlike the rest of the body)

87

Mitral regurgitation

1.problem with the bicuspid AV valve
2. insufficient or leaky valve

88

Mitral regurgitation may be seen

with people that have had rheumatic fever

may need to replace the valve

89

Bicuspid valve AKA

Mitral valve

90

Mitral stenosis

1.could be due to scar tissue or plaque build-up

2. can result in hypertension

91

stenosis

physical narrowing

92

aortic or pulmonary artery stenosis

physical narrowing of either of these two major vessels

93

how to determine mitral regurgitation...

won't sound right

94

veins are (color)

blue

95

arteries are (color)

red

96

Conduction

wave of depolarization

97

ventricles relax (4)

1.pressure drops inside the ventricles
2. semilunar valves close as blood attempts to back up into ventricles from the vessels
3. AV valve opens
4. blood flows from atria to ventricles

98

ventricles contract (3)

1. AV valve close as blood attempts to back up into the atria
2. Pressure rises inside of the ventricles
3. Semilunar valves open and blood flows into great vessels

99

blood enter ____ from superior and inferior __ ___

right atrium from venae cava

100

blood in right atrium flows through ____ into ___

right AV valve (tricuspid)
right ventricles

101

___ of right ventricle forces ____ top open

contraction of right ventricle
pulmonary valve

102

Blood flows through pulmonary valve into ___

pulmonary trunk

103

blood is distributed through the R&L __ to the ___ where it unloads CO2 and loads O2

pulmonary arteries
lungs

104

returns from the lungs via ___ to ___

pulmonary veins
left atrium

105

blood in the left atrium flows through ____ into ___

left AV valve
left ventricle

106

contraction of left ventricles is simultaneous with which step

contraction of right ventricle
which forces open the pulmonary valve

107

contraction of left ventricle forces___

aortic valve to open

108

blood flows through ____ into ascending ___

aortic valve
aorta

109

blood in ___ distributed to every organ in the body where it unloads O2 and loads CO2

aorta

110

The conduction system (5 steps)

1. SA node fires
2.Excitation spreads through atrial myocardium
3. AV node fires
4. Excitation spreads down AV bundle
5. Purkinje fibers distribute excitation through ventricular myocardium

111

Purkinje fibers distribute

excitation through ventricular myocardium

112

SA Node
(AKA)

sinoartial node
pacemaker

113

AV Node
(AKA)

Atrioventricular node

114

the conduction system (2)

1. coordinates the heartbeat
2. generates and conducts rhythmic electrical signals

115

coordinates heartbeat (2)
(conduction system)

1. composed of an internal pacemaker
2. nerve like conduction pathways through myocardium

116

SA node

sinatrial node

117

Sinoatrial node is..

modified cardiocytes

118

SA node does (4)

1. pacemaker initiates each heartbeat
2. determines heart rate
3. pacemaker in right atrium near base of superior vena cava
4. signal spreads throughout atria

119

Atrioventricular node is located

near the right AV valve at lower end of interatrial septum

120

AV node is (2)

1. electrical gateway to the ventricles
2. fibrous skeleton

121

fibrous skeleton

insulator prevents currents from getting to ventricles from any other route

122

Atrioventricular bundle
aka

bundle of his

123

Atrioventricular bundle

Bundle of His
(2)

1. bundle forks into right and left bundle branches
2. branches pass through interventricular septum towards apex

124

purkinje fibers

1. nervelike processes spread throughout ventricular myocardium
2. signal passes from cell to cell through gap junctions

125

nerve supply to the heart

1. sympathetic nerves
2. parasympathetic nerves

126

sympathetic nerves:

increase heart rate
via neurotransmitter norpinphrine

127

sympathetic nerves can speed up heart rate up to

230 bpm

128

parasympathetic nerves:

slow heart rate
via neurotransmitter acetyl choline

129

parasympathetic nerves can slow down heart rate up to

20 bpm

130

sympathetic pathways to the heart originates

in the lower cervical to
upper thoracic segments of the spinal cord

131

parasympathetic pathways begin

with nuclei of the vagus nerves in the medulla oblongata

132

___ % of blood pumped by heart is pumped to the ___

5%
heart

133

the blood pumped to the heart itself through

coronary circulation to sustain its strenuous workload

134

amount of blood pumped to the heart itself

250 mL

135

Angina Pectoris

chest pain from partial obstruction of coronary blood flow

136

Angina Pectoris pain caused by

ischemia cardiac muscle

137

result of Angina Pectoris

myocardium shifts to anaerobic fermentation
producing lactic acid and thus stimulating pain

138

ischemia

lack of blood flow
-injuring tissue
-causes pain

139

heart attack

myocardial infraction

140

myocardial infraction

sudden death of a patch of myocardium resulting from long-term obstruction of coronary circulation

141

atheroma

blood clot
fatty deposit
often obstructs coronary arteries

142

cardiac muscle downstream of blockage

dies

143

signs of a heart attack in men

heavy pressure/ squeezing pain radiating into the left arm

144

(T/F) there are painless heart attacks

(T) may disrupt electrical conduction pathways
leading to fibrillation (irregular/ unsynchronized contraction of heart muscle) and cardiac arrest

145

silent heart attacks occur in

diabetics and the elderly

146

MI are responsible for _ deaths in the United states

half

147

cardiocytes

1. striated, short, thick, branched cells,
2. one central nucleus surrounded by light-staining mass of glycogen

148

intercalated discs

1. join cardiocytes end to end
2. interdigitating folds

149

interdigiating folds

1. folds interlock with each other
2. increase surface area of contact

150

mechanical junctions

tightly join cardiocytes

151

fascia adherens

broad band in which the actin of the thin myofilaments is anchored to the plasma membrane

152

fascia adherens are linked to the next ___

each cell is linked to the next via transmembrane proteins

153

desmosomes

weldlike mechanical junctions between cells

-prevent cardiocytes from being pulled apart

154

electrical junctions
aka

gap junctions

155

electrical junctions
gap junctions

allow ions to flow between cells
can stimulate neighbors
--entire myocardium of either two atria or two ventricles act like single unified unit

156

repair of damage of cardiac muscle is almost entirely by

fibrosis (scarring)

157

cardiac muscle depends almost exclusively on

aerobic respiration used to make ATP

158

cardiac muscle depends on aerobic respiration which is

rich in myoglobin and glycogen
huge mitochondria : fill 25% of cell

159

cardiac metabolism:
adaptable to organic fuels used

fatty acid (60%)
glucose (35%)
ketones, lactic acid
amino acids (5%)
more vulnerable to oxygen deficiency than lack of specific fuel

160

____ because it makes little use of __ or ___

fatigue resistance because it makes little use of anaerobic fermentation or oxygen debt mechanisms
(does not fatigue for a lifetime)

161

first heart sound

tricuspid valve closing
(isovolumetrc contraction)

162

blood from right atrium -->

right ventricle (ventricular filling)

163

pulmonary valve/ semi-lunar valve closed until

critical pressure when forced open
blood goes from right ventricle to pulmonary artery

164

peak right ventricular pressure

is 30 mm Hg

165

ventricular ejection (amount of blood)

70 mL

166

second heart sound

when pressure drops, pulmonary valve closes

167

blood (oxygenated) from pulmonary vein -->

left atrium

168

blood from left atrium -->

left ventricle

169

aortic valve or semilunar valve closed until ..

critical pressure when forced open
blood goes rapidly from left ventricle to aorta

170

peak left ventricular pressure

120 mmHg

171

ventricular ejection

amount of blood
stroke volume
70mL

172

ventricle is not empty it contains

130 mL blood

173

ESV

end systolic volume

174

ESV
end systolic volume

60 mL

175

ESV
passively added to ventricle
during atrial diastole

+30 mL

176

during atrial diastole
added by atrial systole

+40 mL

177

Total: end- diastolic volume (EDV)

130 mL

178

EDV

end diastolic volume

179

SV

stroke volume

180

SV
stroke volume ejected
by ventricular systole

-70 mL

181

ESV

end systolic volume

182

Leaves: End-systolic volume (ESV)

60 mL

183

both ventricles eject _____ amount of blood

the same amount

184

athletes have

lower heart rate

185

athletes are compensated for low heart rate by

increase volume of blood ejected

186

if SA node is damaged: AV node rate

40-50 beats/min

187

if SA node is damaged: purkinje fiber network

rate of 30 beats/min

188

if SA node is damaged: ventricles

rate of 20 beats/min

189

if SA node is damaged: artificial pacemaker

can assume depolarization activity in the heart

190

Cardiac output equation

CO = SV x Heart rate (pulse)
stroke volume beats per minute
mL

191

if heart rate 70 and stroke volume 70

then CO= 4900 mL per minute
or
4.9 L per minute ~ blood volume

192

sedentary person is put on a treadmill

he can increase CO by 4x
most is done by heart rate

193

athletic person is put on a treadmill

he can increase CO by 7-10x
-can SV increase and can also increase HR
-may see CO as high as 35 L/min

194

normal resting position of an athlete with aerobic training can

decrease heart rate to (40-60 bpm) but maintain
CO beacause of the increase in SV

195

three types of muscle

1. cardiac
2. smooth
3. skeletal

196

inherit rhythm

heart cells beat (contract) by themselves
coordinated, synchronized

197

p wave

atrium depolarization

198

Q R S

atria repolarization
*ventricle depolarization*

199

T

repolarization of ventricle

200

2nd Caridac Output equation

(Mean Arterial Pressure (MAP)
-----------------------------------
TOTAL peripheral resistance (TPR)

201

low blood pressure:

raise heart rate - raise blood pressure
exercise will not increase BP
Vessels will dialate (total peripheral resistance)
bigger resistance goes down

202

3 types of receptors

1. sensory
2. cell surface (single molecule)
3. nuclear (single molecule)

203

Auricles

muscular appendages which increase the volume of the atria slightly
-both contain muscular ridges called pectinate muscles

204

left and right coronary artery

supplies the heart with blood

205

great cardiac vein

receives blood from the anterior portion of the heart

206

major internal structures

1. intervenricular septum
very dense
2. bicuspid valve
3. tricuspid valve
4. aortic valve
5. cordae tendineae

207

bicuspid valve also known as

mitral valve

208

cordae tendineae

connects the papillary muscles to the valve cusps

209

ridges within the ventricles

trabecular carnae

210

papillary muscles

contract to open and close the valves
located on the floor of the ventricles

211

tendinous cords

cordae tendineae

212

interatrial septum

very thin

213

epicardium

outer most serous layer of the heart

214

endocardium

innermost layer
which lines the heart chambers and valvular surface

215

myocardium

thickest layer which contains cardiomyocytes and is innervated by the nervous system via the purkinje fibers

216

pericardial fluid

acts as a shock absorber to cushion the heart while beating

217

systemic circulation

1. left atrium
2. left ventricle
3. aoritc arch
4. arteries
5. arterioles
6. capillaries

218

pulmonary circulation

1. inferior/ superior vena cava
2. right atrium
3. right ventricle
4. pulmonary trunk
5. pulmonary arteries
6. respiratory capillaries
7. pulmonary veins

219

coronary circulation supplies the heart with

250 mL of blood at rest

220

arterial supply

1. left anterior descending artery
2. circumflex artery
3. right coronary artery

221

left anterior descending artery

supplies both ventricles and the interventricular septum

222

circumflex artery

supplies the posterior wall of left ventricle and left atrium

223

right coronary artery

supplies right atrium and the sinoatrial node

224

venous return

1. great cardiac vein
2. middle cardiac vein

225

great cardiac vein

collects blood from anterior portion of heart and empties into coronary sinus

226

middle cardiac vein

collects blood from the posterior portion of the heart and drains into coronary sinus

227

blood mixes

in capillaries
otherwise stays separate

228

cardiomyoctye

are the core cells
1. auto- rhythmic, depolarize spontaneously
2. intercalated discs

229

intercalated discs

junction between two cardiac myocytes

230

sinoatrial node

modified cardiomyocytes in the right arm
"pacemaker" for the heart

231

atrioventricular node

acts as an electrical gateway to the ventricles

232

atrioventricular bundle

branches into the right and left bundle branches to serve the right and left ventricles

233

sinus rhythm disorders

bradycardia
tachycardia

234

arrhythmia

abnormal rhythm

235

in order for sinus rhythm to occur

SA node must depolarize

236

SA node sends

excitatory signals to atrial cardiomyocytes which contracts almost simultaneously

237

there is a ___ when the signal reaches the AV node

delay
This occurs because the cells in this region are thinner and there are less gap junctions
--give the left and right ventricles time to fill with blood

238

ventricle contraction is ___

alot slower to try and stay synchronized

239

action potentials in ____ are ____ whereas ____ they are _____

skeletal muscles are quickacting
cardiac muscles are prolonged

240

the contraction is sustained as long

as the cardiomyocytes action potential is in its plateau
this allows for complete emptying of the ventricle

241

cardiac muscle has an absolute refractory period of 250msec

this is to allow for the prevention of wave summation and tetanus which would stop the pumping of the ventricle

242

electrocardiogram

a composite recording of all the heart's electrical activity produced by the nodal and myocardial cells

243

p wave

which is produced when a signal from the SA node spreads through the atria and depolarizes them

244

q

consists of a downward deflection

245

r

tall peak

246

s

another downward deflection

247

QRS complex

the complex represents when the signal from the AV node is produced and travels to the ventricle to depolarize them

248

T wave

the is the ventricular repolarization wave

249

U wave

thought to be repolarization of the purkinje fibers

250

PR interval

used to measure time it takes for the atria to pump blood into the ventricles

251

ST segment

corresponds to the action potential plateau where the ventricles contract and eject blood

252

the contraction is sustained as long as

cardiomyocytes action potential is in its plateau
-this allows for complete emptying of the ventricles

253

repolarization occurs at the

Ca 2+ channels

254

close at the

K + channels

255

open K+

diffuses out of the cell to create a more negatively charged cytoplasm

256

negatively charged cytoplasm

which reduces muscle tension, and starts relaxation for the next round of contraction

257

cardiac muscle has an absolute refractory period of

250msec

258

einthoven's triangle

equilateral triangle
with the heart at its center
its equal sides representing the three standard limb leads of the electrocardiogram

259

einthoven's triangle measures the

mean electrical activity between various points

260

einthoven's triangle is usually

measured at between the right arm, left arm, and left leg

261

normal range of Einthoven's triangle

-30 to +110 degrees

262

Einthoven triangle more positive

is right axis deviation (>110 degrees)
pulmonary hypertension

263

Einthoven's triangle more negative

is left axis deviation ( < -30 degrees)
systemic hypertension

264

EKG does

not represent muscle contraction
measures how much deviates