Chapter 20 - Cardiovascular System - Heart Notes Flashcards
(199 cards)
1
Q
Chapter 20 - Cardiovascular System - Heart
adult heart is the shape of a
A
blunt cone
2
Q
Chapter 20 - Cardiovascular System - Heart
average size of adult heart
A
closed fist
3
Q
Chapter 20 - Cardiovascular System - Heart
blunt rounded point of the cone
A
apex
4
Q
Chapter 20 - Cardiovascular System - Heart
flt larger portion of the cone
A
base
5
Q
Chapter 20 - Cardiovascular System - Heart
heart is located
A
thoracic cavity
6
Q
Chapter 20 - Cardiovascular System - Heart
heart is located between the ________ in a midline partition called the _______
A
lungs
mediastinum
7
Q
Chapter 20 - Cardiovascular System - Heart
what forms the mediastinum
A
heart
esophagus
trachea
associated structures
8
Q
Chapter 20 - Cardiovascular System - Heart
heart lies in a _______ position
A
oblique
9
Q
Chapter 20 - Cardiovascular System - Heart
the apex of the heart is directed to the
A
left
10
Q
Chapter 20 - Cardiovascular System - Heart
approximately _____ of the heart’s mass lies left of the midline of the sternum
A
2/3
11
Q
Chapter 20 - Cardiovascular System - Heart
heart consists of ______ chambers
A
4
12
Q
Chapter 20 - Cardiovascular System - Heart
what are the chambers of the heart
A
two atria
two ventricles
13
Q
Chapter 20 - Cardiovascular System - Heart
the heart is surrounded by a double-layered closed sac called the _________ or _________
A
pericardium
pericardial sac
14
Q
Chapter 20 - Cardiovascular System - Heart
the pericardium consists of ______ outer layer
A
tough fibrous connective tissue
15
Q
Chapter 20 - Cardiovascular System - Heart
name of the outer layer of pericardium
A
fibrous pericardium
16
Q
Chapter 20 - Cardiovascular System - Heart
pericardium has a ________ inner layer
A
simple squamous epithlium
17
Q
Chapter 20 - Cardiovascular System - Heart
name of the inner layer of pericardium
A
serous pericardium
18
Q
Chapter 20 - Cardiovascular System - Heart
function of the fibrous pericardium
A
help hold the heart in place
19
Q
Chapter 20 - Cardiovascular System - Heart
function of the serous pericardium
A
reduce friction as the heart beats
20
Q
Chapter 20 - Cardiovascular System - Heart
the ________ lines the fibrous pericardium
A
parietal pericardium
21
Q
Chapter 20 - Cardiovascular System - Heart
the ________ lines the exterior surface of the heart
A
visceral pericardium
22
Q
Chapter 20 - Cardiovascular System - Heart
_______ is contained in the pericardial cavity between the parietal and visceral pericardium
A
pericardial fluid
23
Q
Chapter 20 - Cardiovascular System - Heart
_______ is inflammation of the serous pericardium
A
pericarditis
24
Q
Chapter 20 - Cardiovascular System - Heart
cause of pericarditis
A
infection
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# Chapter 20 - Cardiovascular System - Heart
what mimics a myocardial infarction
pericarditis
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heart attack
myocardial infarction
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# Chapter 20 - Cardiovascular System - Heart
_______ is an accumulation of fluid in the pericardial sac. when the heart is in its relaxation plase the fluid compresses the heart muscle and it cannot fill with blood to send to the body
cardiac tamponade
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# Chapter 20 - Cardiovascular System - Heart
the heart wall has _______ layers
3
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3 layers of heart wall
outer epicardium
middle myocardium
inner endocardium
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other name of outer epicardium
visceral pericardium
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function of the outer epicardium
provide protection against friction of rubbing organs
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the middle myocardium is composed of
cardiac muscle cells
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function of middle myocardium
contraction
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function of the inner endocardium
reduces the friction resulting from blood passing through the heart
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the inner surfaces of the atria are mainly
smooth
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the _______ have raised areas
auricles
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raised areas on auricles are called
musculi pectinati or
| pectinate muscles
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the ventricles have ridges called
trabeculae carneae
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each atrium has a flap called
auricle
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the atria are separated from the ventricles by the
coronary sulcus
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right and left ventricles are separated by the
interventricular sulcus or groove
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the inferior and superior venae cavae and the coronary sinus enter the
right atrium
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the 4 pulmonary veins enter the
left atrium
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the pulmonary trunk exits the
right ventricle
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the aorta exits the
left ventricle
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_______ branch off the aorta to supply the heart
coronary arteries
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blood returns from the heart tissues to the right atrium through the
```
coronary sinus and
cardiac veins (great and small)
```
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the right atrium has _______ major openings
3
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what are the 3 major openings in right atrium
superior cava
inferior vena cava
coronary sinus
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what travels through the openings in the right atrium
veins from various parts of the body
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the left atrium has _______ openings
4
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what is received in the openings in the left atrium
pulmonary veins
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the atria are separated from each other by the
interatrial septum
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the ventricles are separated by the
interventricular septum
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the right atrium and ventricle are separated bu
tricuspid valve
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the left atrium and ventricle are separated by the
bicuspid or mitral valve
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the cone-shaped muscular pillars are called
papillary muscles
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the papillary muscles are attached to the _______ by _______
atrioventricular valves
| chordae tendineage
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the aorta and pulmonary trunk are seperated from the ventricles by
semilunar valves
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the _______ is the location of the former foramen ovale
fossa ovalis
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where does the mother's oxygenated blood in utero bypass the baby's lungs and go into the left ventricle and out into the body
foramen ovale
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when does the foramen ovale close
1st breath
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_______ is pain that results from reduction in blood supply to cardiac muscles.
* Pain is temporary
* if blood flow restored little to no perm damage
angina pectoris
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characteristic of angina pectoris
*chest discomfort deep in the sternum
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what most often causes angina pectoris
narrowed and hardened coronary arterial walls
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_______ results from a prolonged lack of blood flow to a part of the cardiac muscle resulting in a lack of oxygen and cellular death
myocardial infarction (MI)
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what is time limit to have no cell death occur in a MI
20 minutes
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what is most common cause of MI
thrombus formation that blocks a coronary artery
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_______ partially blocking blood vessels, resulting in turbulent blood flow increase the probability of thrombus formation
atherosclerotic lesions
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_______ is a process whereby a small ballon is threaded through the aorta and into a coronary artery. Inflated, flattening the athersclerotic deposits against the vessel walls, opening the blocked vessel
angioplasty
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_______ is a surgical procedure that relieves the effects of obstructions in the coronary arteries.
coronary bypass
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blood from the body flows through the _______ into the _______, and then flows to the _______.
right atrium
right ventricle
lungs
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blood returns from the _______ to the _______, enters the _______ and is pumped back to the body
lungs
left atrium
left ventricle
74
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the _______ consists of a plate of fibrous connective tissue between the atria and ventricles
fibrous heart skeleton
75
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the fibrous plate forms fibrous rings around _______ and _______ valves
atrioventricular
| semilunar
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function of heart skeleton fibrous plate
solid support for valves
electrical insulation between the valves
point of attachment for cardiac muscles
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cardiac muscles are _______ that contain one or occasionally two centrally located nuclei
elongated branching cells
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_______ and _______ are organized to from _______
actin
myosin
sacromeres
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sacromeres join end to end to form
myofibrils
80
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cardiac muscle cells are joined by
intercalated disks
81
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the _______ of the intercalated disks have folds
membranes
82
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the intercalated disks fit together with adjacent cells, increasing
contact between them
83
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specialized membrane structures called _______ hold the cells together
desmosomes
84
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_______ function as areas of low electric resistance between the cells
gap junctions
85
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the gap junctions allow _______ to move from one cell to the next.
action potential
86
# Chapter 20 - Cardiovascular System - Heart
_______, the cardiac muscle cells behave as a single unit
electrically
87
# Chapter 20 - Cardiovascular System - Heart
cardiac muscles cells have a slow ________ and a prolonged ________ caused by the length of time required for calcium to move to and from the myofibrils
onset of contraction
| contraction time
88
# Chapter 20 - Cardiovascular System - Heart
cardiac muscle is well supplied with blood vessels that support
aerobic respiration
89
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cardiac cells are rich in
mitochondria
90
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what do mitochondria perform
oxidative metabolism
91
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cardiac muscle aerobically use ________, ________, and ________ to produce ATP
glucose
fatty acids
lactic acid
92
# Chapter 20 - Cardiovascular System - Heart
a ________ provides an adequate oxygen supply to the cardiac muscle cells
extensive capillary network
93
# Chapter 20 - Cardiovascular System - Heart
the ________ of the heart, which relays electric action potentials through the heart
conducting system
94
# Chapter 20 - Cardiovascular System - Heart
the conducting system consits of ________ that form two nodes and a ________
modified cardiac muscle cells
| conducting bundle
95
# Chapter 20 - Cardiovascular System - Heart
what is SA node
sinoatrial node
96
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what is AV node
atrioventricular node
97
# Chapter 20 - Cardiovascular System - Heart
where are the SA and AV nodes located
right atrium
98
# Chapter 20 - Cardiovascular System - Heart
the AV node is connected to the bundle branches in the ________ by the AV bundel
interventricular septum
99
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the bundle branches give rise to ________ which are large diameter cardiac muscle fibers
Purkinje fibers
100
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action potentials travel along the ________ much more rapidly than through other cardiac muscle tissue
Purkinje fibers
101
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what initiates action potentials
SA node
102
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action potentials are slowed where
AV node
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# Chapter 20 - Cardiovascular System - Heart
cardiac cells, like neuron and muscle fibers have a
resting membrane potential (RMP)
104
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the resting membrane potential relies on low permeability of the cell membrane to ________ and ________ ions and a higher permeability to ________ ions.
Na+
Ca2+
K+
105
# Chapter 20 - Cardiovascular System - Heart
cardiac muscles fibers exhibit depolarization followed by repolarization of the
RMP
106
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do the action potentials in cardiac muscles last longer/shorter than skeletal muscle
longer
107
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after depolarization and partial repolarization there is a ________, during which the membrane potential only slowly repolarizes
plateau
108
# Chapter 20 - Cardiovascular System - Heart
________ is caused by the movement of sodium ions through the voltage-gated Na+ ion channels
depolarization
109
# Chapter 20 - Cardiovascular System - Heart
________ let sodium ions into the cell to produce the depolarization phase of the action potential
voltage dependent fast channels
110
# Chapter 20 - Cardiovascular System - Heart
________ results from closure of the voltage gated Na+ ion channels
partial repolarization
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the plateau exists because voltage-gated ________ remain open and ________ channels remain closed
Ca2+
| K
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the ________ results from closure of the voltage-gated Ca2+ ion channels and opening of K+ ion channels
rapid phase of repolarization
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cardiac muscles are
autorhymic
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under unusual circumstances, other regions of heart called ________ can initiate beats
ectopic pacemakers or ectopic foci
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________ are widely used clinically in treatment of various cardiac disorders
calcium channel blockers
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# Chapter 20 - Cardiovascular System - Heart
calcium channel blockers do this
reduce autorhymicity of the heart
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calcium channel blocker affect which node
SA
118
# Chapter 20 - Cardiovascular System - Heart
cardiac muscle have a prolonged ________ and ________
depolarization
| refractory period
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# Chapter 20 - Cardiovascular System - Heart
the conduction of action potentials through the myocardium during the cardiac cycle produces ________ that can be measured at the surface of the body
electric currents
120
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what measures these electrical currents
electrocardiogram (ECG)
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how many different waves does ECG record
3
122
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what are the waves of ECG
P wave
QRS complex
T wave
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depolarization of the ________ produces the P wave
atria
124
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depolarization of the ________ produces the QRS complex
ventricles
125
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repolarization of the ________ occurs during the QRS complex
atria
126
# Chapter 20 - Cardiovascular System - Heart
repolarization of the ________ produces the T wave
ventricles
127
# Chapter 20 - Cardiovascular System - Heart
ECG can be used to diagnose
heart abnormalities
128
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the cardiac cycle is
repetitive contraction and relaxation of the heart chambers
129
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blood moves through the circulatory system from areas of ________ to ________ of pressure
higher
| lower
130
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what produces the pressure levels
heart contractions
131
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________ is contraction of a heart chamber
systole
132
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________ is relaxation of a heart chamber
diastole
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________ is the beginning of the cardiac cycle
atrial systole
134
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contraction of the atria complets ________ filling
ventricular
135
# Chapter 20 - Cardiovascular System - Heart
pressure changes in the atria include the ________, the ________, and the ________
a wave
c wave
v wave
136
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a wave caused by
atrial contraction
137
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c wave caused by
ventricular contraction
138
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v wave caused by
blood flowing into the atria
139
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contraction of the ventricles cause blood to move to the ________ and the ________
lungs
| body
140
# Chapter 20 - Cardiovascular System - Heart
pressure generated by the ________ is lower than that generated by the ________.
right ventricle
| left ventricle
141
# Chapter 20 - Cardiovascular System - Heart
right ventricle sends blood to
lungs
142
# Chapter 20 - Cardiovascular System - Heart
left ventricle sends blood to
body
143
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during the period of ________, ventricular contraction causes an increas in pressure within the ventricles, but no movement of blood out of them
isometric contraction
144
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blood flows from the ventricles during
ejection
145
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the period between semilunar valv closure and atrioventricular valve opening, during which no blood flows from the atria into the ventricles is called the period of
isometric relaxation
146
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during diastole blood flows from the atria into the ventricles, increasing the volume of each ventricle to
120-130 ml
147
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as the ventricles empty of blood during systole the volume decreases to
50-60 ml
148
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cardiac output or ________ is stroke volume x heart rate
minute stroke
149
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difference between the cardiac output when a person is at rest and the maximum cardiac output is called the
cardiac reserve
150
# Chapter 20 - Cardiovascular System - Heart
cardiac output is a major factor in determing
blood pressure (BP)
151
# Chapter 20 - Cardiovascular System - Heart
what is critical to maintaining homeostasis
blood movement
| blood pressure
152
# Chapter 20 - Cardiovascular System - Heart
MAP = CO x PR
mean BP = cardiac output x peripheral resistance
153
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________ of the aorta maintains presure in teh aorta and produces ________
elastic recoil
| dicrotic notch
154
# Chapter 20 - Cardiovascular System - Heart
blood pressure measurements reflect the pressure in the
aorta
155
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normal/average blood pressure
120/80
156
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first heart sound
lubb
157
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what produces 1st heart sound
closure of atrioventricular valves
158
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when is 1st heart sound
near beginning of ventricular systole
159
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2nd heart sound
dupp
160
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what produces 2nd heart sound
closure of semilunar valves
161
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when is 2nd heart sound
near end of systole
162
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when is systole
time between 2 heart sounds
163
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when is diastole
between 2nd and 1st heart sounds
164
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occasionally a 3rd heart sound. what causes it
turbulent blood flow
165
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who most often has 3rd heart sound
thin young people
166
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abnormal heart sounds are called
murmurs
167
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_______ have an abnormally narrow opening and produce abnormal heart sounds
stenosed
168
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_______ of the heart valve can cause valves to become either incompetent or stenosed
inflammation
169
# Chapter 20 - Cardiovascular System - Heart
the cardiac output is controlled by regulatory mechanisms classified as either _______ or _______
intrinsic
| extrinsic
170
# Chapter 20 - Cardiovascular System - Heart
_______ results from the normal functional characteristics of the heart and does not depend on either innervation or hormonal regulation
intrinsic
171
# Chapter 20 - Cardiovascular System - Heart
_______ involves neural and hormonal control.
extrinsic
172
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neural regulation of the heart results from _______ and _______ reflexes
sympathetic
| parasympathetic
173
# Chapter 20 - Cardiovascular System - Heart
major hormonal regulation comes from _______ and _______
epinephrine
| norepinephrine
174
# Chapter 20 - Cardiovascular System - Heart
what secretes epinephrine and norepinephrine
adrenal medulla
175
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_______ is the amount of blood that returns to the heart during each cardiac cycle
venous return
176
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_______ describes the relationship between preload and the stroke volume of the heart
Starling's law of the heart
177
# Chapter 20 - Cardiovascular System - Heart
preload is
the extent to which the ventricular walls are stretched
178
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_______ is the pressure the contracting ventricles must produce to overcome the pressure in teh aorta and move the blood into the aorta
afterload
179
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increased venous return does what
stretches the SA node
| increases heart rate
180
# Chapter 20 - Cardiovascular System - Heart
the cardioregulatory center in the _______ regulates the parasympathetic and sympathetic nervous control of the heart
medulla oblongata
181
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parasympathetic stimulation is supplied by
vagus nerve
182
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parasympathetic stimulation does this
decreases the heart rate
183
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sympathetic stimulation is supplied by the
cardiac nerves
184
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sympathetic stimulation does this
increases heart rate
| increases force of contraction
185
# Chapter 20 - Cardiovascular System - Heart
postganglionic neurons secrete _______ in parasympathetic stimulation
acetylcholine
186
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postganglionic neurons secrete _______ in sympathetic stimulation
norepinephrine
187
# Chapter 20 - Cardiovascular System - Heart
sympathetic stimulation release _______ and _______ from adrenal medulla into the blood
epinephrine
| norepinephrine
188
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the effects of hormonal stimulation last _______ than neural stimulation
longer
189
# Chapter 20 - Cardiovascular System - Heart
hormonal stimulation do this
increase the rate and force of heart contraction
190
# Chapter 20 - Cardiovascular System - Heart
the activity of the heart must be regulated because the _______ of the tissues change under such conditions as exercies and rest
metabolic activites
191
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_______ monitor blood pressure
baroreceptors
192
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what do baroreceptors do
change parasympathetic and sympathetic stimulation levels based off blood pressure increases
193
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heart rate increases in response to
stretching of the right atrial wall
194
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_______ monitor blood carbon dioxide, ph, and oxygen levels
chemoreceptors
195
# Chapter 20 - Cardiovascular System - Heart
in response to _______, medullary chemoreceptors increase _______ and decrease _______ of the heart
increased CO2, decreased pH
sympathetic
parasympathetic
196
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_______ stimulated by low O2 levels and results in increased heart rate and vasoconstriction
carotid body chemoreceptors
197
# Chapter 20 - Cardiovascular System - Heart
an increase of decrease in _______ decreases heart rate
extracellular K+ ions
198
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_______ increase the force of cotnraction of the heart and decrease the heart rate.
increased cellular Ca2+
199
# Chapter 20 - Cardiovascular System - Heart
heart rate increases when _______ increases
body temp
