Exam 2 Flashcards
(191 cards)
1
Q
Contractile cardiomyocyte
A
Contractive heart muscle cell
they exert pumping force, have many myofibrils, and have a high ability to contract
2
Q
Conductive cardiomyocyte
A
conductive heart muscle cell
carries signals, few myofibrils and is autorhythmic
3
Q
Myofibril
A
any of the elongated contractile threads found in striated muscle cells
4
Q
Autorhythmic
A
can generate its own rhythm
the heart produces its own pulses through electrochemical stimuli originating from a small group of cells in the wall of the right atrium, known as the sinoatrial node
5
Q
Striated
A
Contractile filaments parallel & highly organized
thick filaments are all in a row in parallel when needs to pul in one direction
6
Q
Glycogen
A
Stored glucose, is in between myofibrils used when the heart needs more glucose to create energy
7
Q
Myoglobin
A
store oxygen in muscle cells, a cell much like hemoglobin but only has 1 polypeptide, used to tie over the heart until blood supply catches up.
8
Q
Anchoring junction
A
part of intercalated discs these junctions are going to hold together the cells. in a picture, they are the dark lines where the cells meet, lock together like velcro
9
Q
Gap junction
A
Part of intercalated discs, they will transmit electrical contraction signals (responsible for electrical charging of cardiac muscle)
Na, K, Ca all can pass through the junctions
10
Q
Conduction system
A
used to establish a heart beat
generate electrical signals & carry them throughout the heart
electrical signals cause contraction
innate rhythm adjusted by neural/endocrine signals
11
Q
Depolarize
A
the cell undergoes a shift in electric charge distribution, resulting in less negative charge inside the cell compared to the outside.
12
Q
Sinoatrial node
A
or pacemaker
13
Q
Pacemaker
A
Otherwise known as the sinoatrial node
is a patch of conductive cells in the superior, posterior right atrium
14
Q
Sinus rhythm
A
normal rhythm of the heart where electrical stimuli are initiated in the SA node
15
Q
Interatrial band
A
or the Bachmann’s bundle, is to the left of the atrium
spread across to both atria, more conductive cells faster pathway to get to left atrium to contract at same time.
16
Q
Bachmann’s bundle
A
otherwise known as the interatrial band
17
Q
Atrioventricular node
A
(AV) node
will receive a signal hold it, and then sends it to the interventricular septum
delays signal so atria finish before ventricles start
18
Q
Internodal path
A
spread of sinus rhythm in three pathways to AV nodes
19
Q
Atrioventricular septum
A
Wall that divides the atrium & ventricle
20
Q
Bundle of His
A
Or AV bundle is on top of the interventricular septum
an elongated segment connecting the AV Node and the left and right bundle branches of the septal crest
21
Q
Atrioventricular bundle
A
Or Bundle of his
22
Q
Interventricular septum
A
the triangular wall of cardiac tissue that separates the left and right ventricles
23
Q
Bundle branch
A
conduct impulses to right and left ventricle (have a R&L)
move down the interventricular septum
24
Q
Purkinje fibers
A
apical ends of branches, up ventricle walls
in walls of ventricles, cause the action of squeezing/pump
gets close to as many contractile cells as possible
25
Action potential
a rapid sequence of changes in the voltage across a membrane
26
Voltage gated channel
the basic ion channels for neuronal excitability, which are crucial for the resting potential and the generation and propagation of action potentials in neurons.
27
sodium channel
transmit depolarizing impulses rapidly throughout cells and cell networks
conductive Na: have slow depolarization
contractile Na: have fast depolarization
28
Threshold potential
the value of the membrane potential which, if reached, leads to the all-or-nothing initiation of an action potential
29
Calcium channel
structural components of cardiac cells that provide a mechanism to modulate the force of contraction
Conductive Ca: Rapid depolarization
Contractile Ca: hold the plateau
30
Potassium channel
particularly important in determining the shape and duration of the action potential, controlling the membrane potential
Conductive K: Repolarization
Contractive K: polarization
31
Repolarize
the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential
32
Resting potential
the electrical potential difference across the plasma membrane when the cell is in a non-excited state
when K+ channels close at -80mV
finish one cycle (causing contraction)
33
Refractory period
Prevents premature next contraction
resistant to open/close channels
34
Plateau period
where Ca2+ and K+ are being released at the same time one going in one going out. K is going slightly faster but Ca causes it to slow repolarization
35
Electrocardiogram
monitoring the electrical signals of the heart
36
P wave
atria depolarize, contracting immediately after
37
QRS wave
atria repolarize, ventricles depolarize
38
T wave
ventricles repolarize causing relaxation
39
compare the number of myofibrils of contractile cardiomyocytes to conductive cardiomyocytes
40
compare the strength of contractile cardiomyocytes to conductive cardiomyocytes
41
compare autorhythmicity of contractile cardiomyocytes to conductive cardiomyocytes
42
How are cardiomyocytes specialized to contract all your life with only short relaxation periods with regard to type of respiration
43
How are cardiomyocytes specialized to contract all your life with only short relaxation periods with regard to number of mitochondria
44
How are cardiomyocytes specialized to contract all your life with only short relaxation periods with regard to oxygen storage
45
How are cardiomyocytes specialized to contract all your life with only short relaxation periods with regard to glucose storage
46
What makes striations in cardiac and skeletal muscles
47
size of cardiac compared to skeletal muscles
48
compare the shape of cardiac vs skeletal muscle
49
compare how many nuclei are in each cell for cardiac and skeletal
50
What are the functions of intercalated disk
51
Why do intercalated discs fold back and forth
52
what is the role of anchoring junctions
53
What are gap junctions for
54
What is the relationship between depolarization and contraction
55
Why is it important to delay the heart depolarization at the AV node
56
Where is the sinoatrial node located
57
How dose the sinus rhythm override spontaneous depolarization of the other conductive cells
58
What influences can increase or decrease the sinus rhythm
59
how does the sinus rhythm depolarization reach the other atrium
60
how does the sinus rhythm reach the AV node
61
How does the AV node alter the rhythm
62
Trace the path of a heart electric stimulus form its origin to its final destinations both in the walls of the atria and in the wall of the ventricles (look at conductive tissues along the way)
63
Why is it essential that Purkinje fivers start ventricular depolarization at the apex of the heart
64
How do Na+ and Ca2+ together account for rhythmic depolarization of a conductive cardiomyocyte, such as those in the SA node
65
How does Na+ channels role differ in contractile myocytes, as compared to conductive myocytes
66
How does Ca2+ channels role differ in contractile myocytes, as compared to conductive myocytes
67
What brings each type of cardiomyocyte up to threshold potential
68
How are gap junctions involved in depolarizing contractile cells
69
what is the refractory period especially important for contractile cardiomyocytes
70
Cardiac cycle
events from start to end of one heartbeat
71
Systole
cambers contract
72
Diastole
Chambers relax
73
Passive ventricular filling
heart itself is not doing any work, the atrium allowing blood into ventricles bc AV are open, SL closed (in diastole)
between T & P wave
gets 70-80% into heart
pressure in veins is higher than that in the heart
74
Atrial systole
Contraction triggered by P wave
AV open, semilunar closed
forces more atrial blood into ventricles
75
Ventricular systole
the ventricles are contracting and vigorously pulsing two separated blood supplies from the heart
76
Isovolumetric contraction
no change in volume, this builds pressure so when the valve opens it can make it all over
events triggered by QRS wave
77
S1
the first sound Lub
the closing of the AV valves results in turbulence in the blood
78
Lub
this is S1
This is the sound that happens when the ventricles contract the back pressure closes the AV valve.
with all valves shut increase ventricular tension & pressure
79
Ventricular ejection
ventricles still contracting, atria still relaxed
the increased ventricular pressure forces semilunar valves to open
80
Isovolumetric relaxation
part of ventricular diastole
instead of building pressure, we are decreasing pressure which closes Semilunar valves to prevent back flow
ventricular diastole triggered by T wave
Relaxation of chambers
81
S2
Closing of the valves & turbulence creates the second heart sound
82
Dub
second sound
83
What forces cause atrioventricular valves to open
84
What forces atrioventricular valves to close
85
What forces the semilunar valves to open
86
what forces the semilunar valves to close
87
what are the names of the heart sounds
88
What causes each heart sound
89
What are the five phases of the cardiac cycle
90
Cardiac output
Blood/min= HR * SV (4-8 L/min)
91
Stroke volume
blood from ventricle/ beat, 55-100 mL
(tennis swing)
92
Heart rate
Beats/min 60-100 bpm
can be affected by nerves, hormones
93
Echocardiogram
ultrasound for the heart
94
Ejection fraction
is the fraction pumped out by the ventricle
calculated by SV/ total volume (EDV) x 100
95
End diastolic volume
volume after heart was resting
96
End systolic volume
volume after ventricular systole, amount after contraction
97
Bradycardia
low heart rate
98
Tachycardia
High heart rate
99
Target heart rate
To hold the maximum Cardiac output it is 50-80% of the max heart rate
100
cardiac reserve
is the maximum cardiac output - resting cardiac output
101
Proprioceptor
are receptors in joints, tendons & muscles
they will sense our position (close eyes and touch nose)
ex. working out need to increase CO
102
Baroreceptor
measures blood pressure
pressure receptors are sinuses
measures arterial pressure, systemic circulation pressure, and pressure in the aorta
103
Aortic sinus
The baroreceptor is in the aortic sinus
one of the anatomic dilatations of the ascending aorta, which occurs just above the aortic valve
104
Carotid sinus
a dilation at the base of the internal carotid artery
105
Cental Chemoreceptor
measures CO2, pH in the blood, located in the medulla oblongata
106
Peripheral chemoreceptor
measures CO2, pH, and O2 in aortic and carotid bodies
107
Aortic body
a collection of nonchromaffin paraganglion cells
next to barorecepters
108
Carotid body
a small mass of receptors in the carotid artery sensitive to chemical change in the blood
109
Parasympathetic system
Used to slow down cardiac output
rest and relax
110
cardioinhibitory center
placed in the medulla oblongata is going to inhibit cardiac output
(slows cardiac function by decreasing heart rate and stroke volume)
111
Medulla oblongata
the bottom-most part of your brain. Its location means it's where your brain and spinal cord connect, making it a key conduit for nerve signals
112
Vagus nerve (Cranial nerve X)
Path for efferent signal in the parasympathetic pathway, to the cardiac plexus
113
Cardiac plexus
A bunch of nerves at the base of the heart formed by cardiac branches from sympathetic and parasympathetic systems
114
Acetylcholine
hyperpolarizes the myocardium
the neurotransmitter in parasympathetic system
115
Neurotransmitter
send signals
116
Sympathetic system
fight or flight, one of the divisions of the autonomic nervous system
activates when heart rate is too low
117
Cardioacceleratory center
going to send the signal to speed up the heart rate and cardiac output
located in the medulla oblongata
118
Chain ganglia
is a collection of neuron cell bodies outside the CNS beside the spinal cord going in a chain down the spinal cord
119
Cardiac nerve
goes from the chain ganglia to the cardiac nerve that will run from the spinal cord to the heart
120
Norepinephrine
is a neurotransmitter used in the sympathetic nervous system
is used to reduce repolarization of myocardium
121
Atrial (Brainbridge) reflex
also called atrial reflex
stretch indicates venous return tighter than cardiac output
increase the heart rate to increase cardiac output to catch up to venous return
122
Preload
pressure in ventricles from end-diastolic volume
123
Contractility
Fore of the contraction fo the heart muscle
more pressure in the ventricles going to push harder
124
Starling's law
higher pressure --> greater contractility
125
Afterload
pushing harder to get blood out
resistance in arteries to ventricular ejection decreases SV
Back pressure on semilunar reduces stroke volume
126
Stenosis
"narrowing", stiffening
stenosis will increase afterload and reduce SV
127
Vasular resistance
the amount of force exerted on the blood by the vessels
128
Atherosclerosis
another word for vascular constriction
will increase afterload
129
Tunica intima
the luminal surface
endothelium layer made up of a simple squamous epithelium
Basement membrane
areolar tissue
internal elastic membrane
130
Another name for Tunica intima is...
tunica interna
131
Epithelial membrane
the innermost part of the luminal structure
132
Endothelium
simple squamous epithelium
133
Basement membrane
binds to the epithelial layer and binds underlying C.T
134
Areolar tissue
loose fibrous connective tissue
has a fenestrated internal elastic membrane
135
Internal elastic membrane
used to help stretch when the ventricles pump, is zigzag ish in structre
136
Fenestration
small holes that will allow for O2 & CO2 to pass through
137
Tunica media
muscular layer, like the myocardium in heart
smooth muscle for vasoconstriction
138
Vasoconstriction
will constrict the blood vessels to increase pressure and decrease flow
139
Vasodilatation
when the smooth muscle relaxes, will increase flow and decrease BP
140
Myofiber
muscle fibers, in between them is collagen & elastic fibers
141
vasa vasorum
embedded vessels for superficial layers
blood vessels of blood vessels
in tunica media
142
Nervi vasorum
sympathetic nerves control the smooth muscle
in the tunica media
143
External elastic membrane
fenestrated to allow for gas exchange same as internal
144
Tunica externa
areolar connective tissues anchor vessels in place
has nervi vasorum & vasa vasorum
145
What is another name for tunica externa?
Tunica adventitia
146
Elastic artery
conduct blood to different parts of the body
nearest to the heart, stretch to absorb hart force during systole, then rebounds to maintain flow in diastole
147
What is another name for the elastic artery?
Conducting artery
148
Muscular artery
slight change
branch from elastic, more muscles, less elastic fibers, muscle allows for vasoconstriction & BP management
149
What is another name for the muscular artery?
Distributing artery
150
Arteriole
can control blood flow (major role in BP)
less tunica media, large numbers & length reduces blood pressure, critical in control of local blood distribution
151
Another way to describe the arteriole is....
resistance vessel
152
Capillary
Tunica intima only, site of gas exchange
three different types (continuous, fenestrated, sinusoids)
153
Continuous capillary
common, clefts only between endothelial cells
154
Fenestrated capillary
clefts, pores in kidneys, intestines, glands, and choroid (cerebral spinal fluid maker)
155
Sinusoid
fenestration, gaps
located in the marrow, liver, spleen & endocrine glands
156
Venule
collect blood from capillary beds
thin tunica external & tunica media
157
Venoconstriction
constricting of the veins
used to adjust blood reservoir function
158
Blood pressure
(BP)
159
Blood flow
(Q)
160
Vascular resistance
(R)
161
Systolic pressure
peak arterial pressure at systole
162
Diastolic pressure
minimum arterial pressure at diasole
163
pulse pressure
systolic - diastolic pressure
0 with distance
164
Mean arterial pressure
the diastolic pressure + (pulse pressure/3)
165
Sphygmomanometer
blood pressure cuff
air cuff pressure occludes the artery
166
Korotkoff sounds
sounds made by the squirting of blood through partially occulted artery
167
Viscosity
how thick the blood is
increase in viscosity, increase R
harder to push through blood vessels (polycythemia increase v, liver damage decrease v)
168
Compliance
(C)
how easily does it stretch
more compliance decreases resistance, increases flow & decreases pressure
169
Arteriosclerosis
reduces compliance and increases BP
it is the stiffening of the arteries, which can cause a build-up of blood that can cause a thrombosis/embolus
170
Cross-selection area
(A)
how big around something is
more cross-section decreases resistance, pressure, velocity & BP, it will increase flow
171
Blood velocity
the distance at which the blood moves
172
Hypervolemia
too much blood volume
by water and salt retention
ex kidney disease
173
Hypovolemia
by dehydration, bleeding, vomiting, diarrhea
174
Skeletal muscle pump
veins b/w skeletal muscles or b/w muscle & bones, when contracted will squeeze blood toward the heart, have one-way valves to prevent backflow
175
Respiratory pump
when inhaled decreases the pressure in the thoracic, causing the blood to move from the abdomen to the chest (high to low), then exhale it increases the pressure in the thoracic cavity pushing the blood into the atrium where there is less pressure
176
Direct diffusion
movement from high to low [ ]
molecules that are uncharged or non-polar, also ones that are hydrophobic
oxygen, carbon dioxide
177
hydrophobic molecules
lipids, steroids, fat-soluble vitamins
178
facilitated diffusion
small molecusles that are charged (polar), and hydrophilic
go through a transport protein
179
transport protien
hydrophilic on the inside, hydrophobic on the outside
can open and close like a window
180
vesicular transport
larger particles (proteins)
can store stuff in the membrane, a bubble inside the cell
181
endocytosis
process inside the cell (getting inside the cell)
182
exocytosis
process on the other side of cell to leave/ release
183
transcytosis
the whole process of endo & exo across the cell is transcytosis
getting a protein from liver cells to the blood vessels
184
bulk flow
movements of liquids (water, solutes, colloids) b/w gaps in epithelium
185
filtration
186
hydrostatic pressure
187
Reabsorption
188
Colloid
189
Colloid osmotic pressure
190
Net filtraiton pressure
191
Lymphatic system
