Exam 3 Flashcards
1
Q
what is myoglobulin
A
a red protein that is capable of binding w/ oxygen when there is low amounts of oxygen in the blood needed for phosphorylation
2
Q
what produces ATP in the muscle cells
A
glycolysis, oxidative phosphorylation, and beta oxidation
3
Q
in what form is glucose stored inbetween myofibrils
A
glycogen
4
Q
what is ATP used for in skeletal muscle
A
both contraction and relaxation
5
Q
what allows for a rapid generation of ATP
A
Creatine phosphate
6
Q
what material are broken down in the TCA cycle that is processed in oxidative phosphorylation
A
FA, AA and glycolysis
7
Q
what is creatine phosphate (phosphocreatine)
A
the first energy reservoir tapped at the onset of contractile activity in vertebrates skeletal muscle
8
Q
what does phosphogens contain that can be quickly donated to ADP
A
a high energy phosphate group
9
Q
how much creatine phosphate do vertebrake skeletal muscle contain compared to ATP
A
5x as much
10
Q
where in the cell does oxidative phosphorylation occur
A
the mitochondria
11
Q
what is required for oxidative phosphorylation
A
oxygen and light to moderate aerobic activity
12
Q
what materials fuel oxidative phosphorylation
A
FA, glucose, and myoglobin
13
Q
what type of yield is oxidative phosphorylation
A
rich yield
14
Q
does oxidative phosphorylation take more or less time
A
more due to being a multistep pathway
15
Q
where in the cell does gylcolysis occur
A
in the cytoplasm
16
Q
can glycolysis produce ATP w/o oxygen
A
yes
17
Q
what fuels glycolysis
A
glucose and high intensity anaerobic activity
18
Q
what type of yield is glycolysis
A
a low yield
19
Q
does glycolysis take more or less time
A
less
20
Q
what does glycolysis produce other than ATP
A
lactate and accompanying acidosis
21
Q
how can skeletal muscle fibers be characterized
A
contractility, oxidative capacity, and myoglobin content
22
Q
what is the contractility of the muscle fibers based on
A
the speed at which the myosin can hydrolyze ATP
23
Q
what does the speed of myosin reflect
A
the ATP hydrolysis rate
24
Q
what does MHC mean
A
myosin heavy chain
25
what type of muscle is skeletal muscle considered
type 2
26
what is the one type of skeletal muscle that is considered type one
skeletal slow twitch
27
what type is cardiac MHC alpha considered
Fast two
28
what type is cardiac MHC beta considered
type one
29
what type is smooth muscle considered
type one
30
t/f most muscle cells are considered heterogenous meaning it contains both slow and fast fibers
true
31
what are the characteristics of type one muscle fibers
slow ATPase rate, fewer myofibrils, adapted for long slow contractions, and contains large amounts of mitochondria and myoglobin
32
what are the characteristics of type two muscle fibers
fast ATPase rate, faster muscle contractions, more myofibrils, and less myoglobin
33
what does more myofibrils mean
more surface area which means more force
34
what are the two subdivisions of type two fibers
Type 2a and Type 2b
35
what are the characteristics of Type 2a muscle fibers
large amounts of mitochondria and myoglobin and being utilized during aerobic respiration
36
what are the characterisitics of Type 2b muscle fibers
few mitochondria w/ little to no myoglobin (very light), rely on glycolysis for ATP production, and are utilized during anaerobic glycolysis
37
t/f: muscles that produce less force do not generate their ATP as efficiently as fibers that produce more force
false, muscle fibers that produce more force do not generate their ATP as efficiently
38
what do myosin activity, oxidative capacity, and myoglobin content directly effect in skeletal muscle
their tendency to exhibit fatigue
39
what two systems is the circulatory system is divided into
pulmonary and systemic ciculatory systems
40
where does deoxygenated blood get reoxygenated
passing thru the arterioles to the venules located in the lungs
41
where does all the oxygenated blood get deposited
from arterioles to venules in the remaining tissues found in the abdomenial cavity
42
what does the dissolved gas level look like with oxygenated blood
more dissolved oxgen w/ less CO2
43
what does the dissolved gas level look like with deoxygenated blood
less dissolved oxygen w/ more CO2
44
where does the pulmonary system have high pressure
when the oxygenated blood is getting pumped out of the left ventricle and when the deoxygenated blood is getting pumped into the lungs
45
where does the pulmonary system have low pressure
when the oxygenated blood is leaving the lungs and when the deoxygenated blood is being pumped back into the right atrium
46
describe the movement of the heart
the blood passes through the systemic circuit the blood is now partly deoxygenated flowing into the venae cavae into the right atrium then into the right atrioventricular valve to the right ventricle. Which then pumps the deoxygenated blood through the pulmonary valve into the pulomonary trunk, flowing into the lungs in the pulmonary ciruit. The reoxygenated enters thru the pulmonary veins into the left atria thru the left atrioventricular valve to the left ventricle. which pumps the oxygenated blood to the aortic valve into the systemic aorta to the entire systemic circuit.
47
what are the jobs of the atrioventricular valve and the pulmonary/atrial 'semilunar' valves
to prevent backflow
48
describe how the heart is a pressurized system
the heart creates a pressure wave w/ each contraction to push blood thru the arteries which dissipates as it goes thru the plumbing of the tissues
49
what is the direction of flow
from the heart to artery to arteriole to capillary to venule to vein back to the heart
50
how can vessels handle high pressure
they have lots of connective tissues allowing them to flex and stretch as well as lots of smooth muscle cells giving them great control
51
what is the definition of systole
when the heart is in the phase of contracting
52
what is the definition of diastole
when the heart is in the phase of relaxing and being filled with blood
53
which is shorter systole or diastole
systole
54
what does hydrostatic pressure do
it pushes material out
55
what does osmotic pressure do
it pulls material back in
56
what is the covering separating the heart from the other structures in the thoracic cavity
pericardium
57
where are the superior and inferior venae cavae, aorta, and pulmonary trunk located on the heart
the superior surface (base)
58
what is the apex
the most distal part of the left ventricle (point)
59
what are the two distinct layers of the pericardium
the fibrous and the serious
60
what two sublayers does the serious pericardium consist of
the parietal and the visceral
61
what is another name for the visceral pericardium
epicardium
62
what is the pericardial cavity
a lubricating fluid that keeps the parietal and visceral from rubbing against each other
63
what is the order of layers of pericardium going from outside in
fibrous, pericardium cavity, parietal, and visceral
64
what is the definition of the fibrous pericardium
connective tissue that protects the heart and maintains its position in the thorax
65
what is the majority of the heart made out of
myocardium
66
what is the endocardium
lines the chambers where the blood circulates and covers the heart valves made of endothelium which lines the blood vessels as well
67
what is the septum
a physical extension of the myocardium lined w/ endocardium
68
what are the two atria separated by
the interatrial septum
69
what are the two ventricles separated by
the intraventricular septum
70
what is the atrioventricular septum
the septum between the atria and ventricles
71
how do the semilunar valves open to allow bloodflow
as the ventricles contract and intraventricular pressure rises blood is pushed up agains semilunar valves forcing them to open
72
how do the semilunar valves close
as ventricles relax and the intraventricular pressure falls blood blows back from arteries filling the cusps of semilunar valves and forcing them to close
73
describe what is happening when the second heart beat occurs
the contraction is ending and the pressure wave causes blood to rush into the large arteries causing a back pressure the blood will then catch the cusps of the valve and snap them close keeping the directional flow
74
what is chordae tendinae
connective tissue connected to the atrioventricular valves that reinforces the valve to reduce risk of aversion caused by the pressure produced by the ventricles
75
what is papillary muscles
projections from the wall of the heart that attach to the chordae tendinae to provent prolapse of the AV valve leaflets during ventricular systole
76
why is the muscle of the left ventricle thicker then the muscle of the right ventricle
the left ventricle requires mores force to be able to push the blood to the rest of the body while the right ventricle just has to push blood to the lungs
77
what do P waves represent on an EKG
the action potentials that are sweeping thru the atria
78
what is the QRS complex on an EKG
the action potentials sweeping thru the ventricles
79
what does the T wave represent on an EKG
the repolarization of the ventricle
80
where do you see the repolarization of the atria
hiddne in the QRS complex
81
what is the isovolumic contraction
the pressure is building but the volume does not change due to the pressure in the aorta still being higher
82
what are the semilunar valves
the pulmonary and aortic valves
83
what are the atrioventricular valves
the tricuspid and bicuspid valves
84
t/f: the heart is capable of auto rhythmicity
true
85
what systems is the heart rate modulated by
the endocrine and nervous systems
86
what are the two types of myocardial cells
contractile and conducting
87
what are contractile cells
they consitute most of the atria and ventricles that undergo action potentials; pump the blood thru the body
88
what are conducting cells
a small portion of the myocardial that initate and propagate action potentials that travel throughout the heart
89
what are intercalated disks
the connect cardiac muscle cells to one another as well as hold protein complexes
90
what are macula adherins similar to in regards to function
desmosomes
91
what are fascia adherins similar to in regards to function
adheren junctions
92
what does a lack in terminal cisterne mean for cardiac muscle
it does not interact w/ the t tubule as much
93
describe the Ca induced Ca release in cardiac muscle contraction
there is an influx of Ca from the ECF via the T-tubules that further stimulates the release of Ca from the SR
94
what two nodes initiate and propagate the contractions of the heart
the sinoatrial and the atrioventricular
95
where is the AV node located in the heart
at the boundary between the atria and ventricles
96
where are the SA node located in the heart
the wall of the right atrium
97
t/f: the AV bundle runs down the intraventricular septum as one contiunous conduit
false, at it runs down the septum to the apex it divides into the left and right AV bundles connecting to their respective ventricles
98
what are Purkinje fibers
the branches of the left and right AV bundles that project into the contractile cells allowing for synchronous contraction
99
what is considered the pacemaker of the heart
the sinoatrial node
100
t/f: all conduction cells are capable of creating a spontaneous contraction
true
101
why cant action potentials move thru the atria ventricle septa
because it is connective tissue
102
describe the initiation and spread of depolarization during a heartbeat
depolarization begins in the SA node spreading outward thru the atrial muscle however the spread into the AV node is delayed and the depolarized atria starts to contract. Once the AV node is depolarized the depolarization spreads rapidly to the ventricles, during this time the atrial muscle starts to repolarize. Finally the nearly simultaneous depolarization w/in the ventricular myocardium leads to a strong ventricular contraction
103
what is the only structure that can transfer action potentials from the atria to the ventricles
the AV node
104
what is the purpose of the delay in the spread of action potentials between the atria and the ventricle
this is so the blood has time to be pushed from the atria to the ventricle
105
how does the wave of depolarization propagate to the ventricular cells in the myocardium
thru gap junctions
106
what type of channel is responsible for inducing an action potential in cardiac muscle
voltage gated long lasting Ca channels
107
is the membrane potential in cardiac muscle typically higher or lower
higher
108
what is the status of the Na, K, and Ca channels when the membrane potential of pacemaker cells depolarize
there is an increase in Na (for hyperpolarization) and Ca followed by a outflux of K
109
does cardiac muscle have a resting membrane potential
NO
110
when do funny channels open
during hyperpolarization
111
what is the proper name for funny channels
HCN channels or hyperpolarization activated cyclic nucleotide gated channels
112
what causes the long plateau phase only found in cardiac muscle cell action potentials
an influx in Ca (the key factor of a contractile action potential)
113
describe the rising phase of a cardiac action potential
these are phases 0 & 1 where the fast Na channels open to allow rapid flow to depolarize the cell then the Na channels become blocked and the K channels open for repolarization
114
describe the plateau phase of cardiac action potentials
this is phase 2 where the slow L type Ca channels open prolonging contraction and the K channels close
115
describe the falling phase of cardiac action potentials
this is phase 3 where the Ca channels close and the voltage gated K channels reopen
116
what is a better name for the "resting potential" for contractile cells
pacemaker potential
117
in the ventricules what channel starts the spread of an action potential
voltage gated Na channels
118
describe the steps of excitation contraction coupling in the heart
Ca enters the cytosol thru L type Ca channels in the membrane and t tubules which triggers the release of Ca from the SR once in the cytoplasm Ca binds to troponin-tropomyosin complex allowing the cross bridge cycle to occur
119
what is the extent and duration of the cross bridge activiy based on in cardiac muscle
the amount of cytosolic Ca
120
does cardiac muscle have a long or short refractory period
long (about 250 seconds)
121
what occurs during a cardiac refractory period
the Na channels remain inactive during the plateau phase preventing summation of contractions and tetanus
122
what is tetanus
a phenomenon where there is a maximal sustained contraction for a certain period of time
123
why is tetanus very bad for the heart
tetanus does not allow muscle to relax if this were to occur in the heart it would not be able to fill the ventricle w/ blood
124
what are funny channels the basis for
spontaneous depolarization
125
how does the sympathetic nervous system stimulate the SA node
A G protein is used as a secondary messenger to open beta receptors stimulating the release of Dentoalocyclase producing cAMP which then binds to the funny channel making it easier to open followed by PKA which then phosphorylates the L type voltage gated Ca channels
126
how does the parasympathetic nervous system stimulate the SA node
Muscarinic receptors produce Acetylcholine that binds to G proteins the receptors antagonize cAMP as well as opening voltage gated K channels resulting in a depolarization slowing the rate
127
what are the responses of contractile cardiomyocytes to the sympathetic stimulation
Phosphorylation of Ca channels in the plasma membrane causes the Ca channels to remain open during longer action potentials then proteins in the SR enhances release of Ca myosin then increases in the rate of myosin ATPase the speed at which the Ca pumps normally function is increased speeding up the re uptake of Ca into the SR and ECF
128
what affects does ACH have on the HR
it slows the rate of spontaneous depolarization by opening K channels
129
what affects does NE and E have on the HR
it increases the rate of spontaneous depolarization by making HCN and VGCC channels more likely to open
130
what carries deoxygenated blood from the rest of the body back to the heart which is then pumped to the lungs by the right ventricle
veins
131
what carries oxygenated blood from the lungs to the heart to be pumped to the rest of the body by the right ventricle
arteries
132
what is a portal system
a vessel that directly connects two capillary beds
133
what are the similarities between arteries and veins
contains a lumen and has multiple layers
134
what are the differences between arteries and veins
shape, thickness of the tunica interna, the presence of elastic membranes
135
what are the three layers of an artery wall
tunica externa, tunica media, tunica interna
136
define the tunica intima
the inner layer of the wall that comprises of endothelium, the subendothelial connective tissue, and the internal elastic lamina
137
define the tunica media
the middle layer of the wall that comprises of smooth muscle cells, elastic lamellae including the external elastic lamina and collegen fibers
138
define the tunica externa
the most outer layer that comprises of connective tissue, macrophages, mast cells, fibroblasts, and the nerves and vessels that supply the vascular wall
139
what type of cells do arteris contain the most of
smooth muscle cells
140
what is the thickest layer in veins
the tunica externa
141
how does the endothelium of the tunica intima appear in arteries
wavy
142
how does the endothelium of the tunica intima appear in veins
very smooth
143
what is the thickest layer in arteries
the tunica media which contains smooth muscle cells and elastic fibers
144
what does the tunica media contain in veins
smooth muscle cells, collagenous fibers, Nervi vasorum, and vasa vasorum
145
what does the tunica externa contain in arteries
collagenous, elastic fibers, nervi vasorum, and vasa vasorum
146
what are the characteristics of elastic arteries
they have more elastic fibers and smooth muscle cells
147
what are the characteristic of muscular arteries
a high concentration of smooth muscle cells
148
what are the characteristics of arterioles
they have one or two layers of smooth muscle cells, an interanl elastic lamina, and have a small tunica externa, contains a thin layer of collagen and isolated elastic fibers
149
where does the exhange of gasses and nutrients takes place
the capillaries
150
what are pericytes
perivascular cells that wrap around blood capillaries, small arterioles, and venules
151
t/f: pericytes can constrict and dilate associated capillaries
true
152
what do gap junctions connect in capillaries
the cytoplasm of endothelial cells and pericytes
153
what are the three types of capillaries
continuous, fenestrated, and sinusoid
154
describe continuous capillaries
intact endothelium w/ no major gaps containing intercellular junctions to help the cell membrane allow certain materials pass thru example is muscle cells
155
describe fenestrated capillaries
they have microscopic holes in them allowing solutes to move more freely between them other than water soluble molecules example is kidneys
156
describe sinusoid capillaries
they have major gaps in the endothelium allowing for passage of large molecules example is bone marrow
157
what are the thinnest capillaries important for
oxygen diffusion
158
what are venules essentially
tubes of endothelium that are either surrounded by pericytes (small) or one to two layers of smooth muscle cells (large)
159
what structure is present in veins to help directionality
valves
160
how do skeletal muscles assist in moving blood back to the heart
the contraction pushes blood past open valves
161
where is the majority of the blood volume located in the body
the systemic circulatory system
162
t/f: the systemic veins are not able to easily store a high volume of blood even at a low pressure
false, they are capable of expanding easily allowing them to have a high volume even at low pressure
163
what are veins examples of
blood reservoirs
164
what are blood reservoirs
excess blood that can be mobilized when needed particularly when the blood volume is low these include the spleen, liver, larger abdominal veins, venous plexus beneath the skin
165
what does increased blood returning to the heart increase
end diastolic volume
166
what is a metarteriole
a branch from the arteriole that meets w/ the thoroughfare from the venule that is the main point of gas exchange in capillaries
167
what are precapillary spincters
smooth muscle cells that broken away from the arteriole into the capillary bed forming a ring of smooth muscle around the blood vessels
168
what is a vascular shunt
when the sphincters contract cutting off the blood from the capillaries forcing the blood back into the venule
169
what is autoregulation of BP
when the brain or heart tells sphinters to constrict blood flow in the capillaries of extremities in cold temperatures
170
how do you find the MAP
take the diastolic plus the pulse pressure then divide it by 3
171
what do continuous capillaries have in their cell membrane that allows for diffusion of water and other small materials
slit like gaps/clefts
172
how are plasma proteins such as albumin passed thru the cell membrane
they are packaged by the cell membrane then fused w/ the plasma membrane then diffused in the ICF
173
how are exchangeable proteins moved thru the cell membrane
thru the vesicular transport
174
what is interstitial fluid a result of
the blood filtering thru the capillaries maintaining homeostasis by pushing some of the liquid in the veinous of the capillaries derived by filtration and diffusion
175
how is interstitial fluid compare to plasma
it contains all the same components but is lower in the concentration of proteins
176
what are proteoglycan filaments
thin coiled or twisted molecules composed of about 98% hyaluronic acid and 2 % protein
177
what is the consistency of proteoglycan filaments
gel like
178
what is the formula for ECF
plasma + interstitial fluid
179
what qualities does the filtration from the heart have
high MAP, rich oxygen, and rich in nutrients
180
what qualities does reabsorption to the heart have
low MAP, poor in oxygen, and poor in nutrients
181
what is bulk flow
the mass movement of fluids into and out of capillary beds requires transport processes that are more efficient than diffusion alone
182
what is filtration
how fluid moves from an area of higher pressure in a capillary bed to an area of lower pressure in the tissue
183
what is reabsorption
the movement of fluid from an area of higher pressure in the tissues into an area of lower pressure in the capillaries
184
t/f: small molecules can create an osmotic gradient
false only large molecules
185
what does an increase in pressure in the atria end show
a net increase in hydrostatic pressure
186
what does an increase in pressure in the venous end show
a net decrease in osmotic pressure
187
what does a high albumin in the area of gas exchange equal
an increase in venous pressure
188
what generates hydrostatic pressure
gravity and blood pressure
189
what does hydrostatic pressure create
Net Filtration Pressure (NFP)
190
what generates osmotic pressure
plasma proteins
191
what does mean capillary pressure typically stay at
17 mm Hg
192
what is blood pressure
the measurement of the pressure or force of blood inside your arteries
193
what is the formula for blood pressure
cardiac output (C.O) * total peripheral resistance (T.P.R)
194
what is the formula for cardiac output
heart rate * stroke volume
195
what things can increase heart rate
sympathetic nervous system, hormones, and ions
196
what things can decrease heart rate
parasympathetic nervous system and ions
197
what is are the three aspects to stroke volume
preload, contractility, and afterload
198
what is preload
volume of the blood that reaches the heart
199
how can preload be increased
by drinking water and increasing the mobilization from blood reservoirs from various organs in the body
200
what does a greater stretch of the heart muscle do
it allows the heart to use a greater force when pushing blood to the rest of the body
201
what is contractility
the addition of hormones and chemicals in the blood such as epinephrine and T4 will increase the stroke volume
202
what type of control increases venous return to affect end diastolic volume and later stroke volume
intrinsic control
203
what control increases sympathetic activity
extrinsic control
204
what is the formula for flow
delta P/R
205
what is pressure differential called
pulse pressure
206
what is the formula for resistance
8nL/pier^4
207
what directly affects the resistance
viscosity of blood, the length of blood vessels, and radius of the vessels
208
what has the biggest affect on resistance
the radius of the vessels
209
what is vasoconstriction
when the diameter/radius of blood vessels is constricted decreasing blood flow
210
what is vasodialation
when the diameter/radius of blood vessels are dialated to increase blood flow
211
what are important evolutionary adaptations that are required to breath in air
lungs, alveoli that are coated w/ water, and mucus coats
212
what is the role of mucus coats
they are designed to keep the upper respiratory tract moist
213
what happens when you breath
you create a negative pressure that allows passive effusion to take place
214
what is the role of the epiglottis
to close off the trachea keeping food from entering the lung and vis versa w/ the esophagus
215
what is the path of external respiration
from the nose to the sinuses to the trachea
216
what critical adaptation does the trachea have and what is its purpose
the hyaline cartilage keeps the structure of the trachea as negative and positive pressure causes it to collapse and expand
217
what is the carina
the ridge of cartilage that contains specialized nervous tissue that induces violent coughing if foreign material contacts it
218
what are bronchi
they are progressive branches in the lungs that eventually become terminal bronchioles and respiratory bronchioles
219
what is found at the end of the bronchioles
alveolar sacs
220
what is the alveoli
sacs where true respiration takes place via gas exchange
221
what is the cardiac notch
a space present on the left lung due to it sharing space w/ the heart
222
what truly allows for the alveoli to deposit oxygen into RBC's
capillaries running across the alveoli and connecting to them
223
what is the respiratory membrane
where the capillary wall meets the alveolar wall
224
what are alveolar pores
they connect neighboring alveoli to each other to help maintain equal air pressure throughout the lung
225
what are type 1 alveolar cells
a squamous epithelial cell of the alveoli that constitutes most of the alveolar surface area
226
what are type 2 alveolar cells
the secrete pulmonary surfactant a substance that reduces the surface tension of the alveoli and they work interspersed among type 1 cells
227
what are alveolar macrophages
the remove debris and pathogens that have reached the alveoli they are considered phagocytic cell of the immune system
228
what is the unit of air exchange in lungs
the air blood
229
what makes up the respirtory membrane
epithelial cell and type 1 alveolar cells
230
what is a distinct feature of type 2 alveolar cells
they consist of lamellar bodies that contain phospholipid precursors to pulmonary surfactant
231
why do water and air molecules have a high attraction for each other in the lungs
hydrogen bonding
232
what does lung (pulmonary) surfactant greatly reduce
the surface tension of water
233
what is pulmonary surfactant
a major phospholipid called (DPPC) that consists of two C16 palmitic acid groups attached to a phosphatidylicholine head group
234
what happens to surface tension w/o surfactant
the attractive forces create high surface tension pulling molecules together causing a collapse
235
what are the three roles of surfactant
regulate alveolar size, keeps alveoli dry, and participates in innate immune function
236
what is opsonization
protein that can bind to the back of bacteria which are then targeted by phagocytes
237
what is the visceral pleura
the layer that attached to the lungs
238
what is the parietal pleura
the outer layer that connects to the thoracic wall, the diaphragm, and mediastinum
239
what is the function and location of the intercostal muscle
it surrounds the pleural cavity and it pulls down the rib cage and pushes air out of the lung
240
what is the purpose of the small gap between the lung tissue and the intercostal muscle
it contains a small amount of fluid keeping the organs moist
241
is the lung directly attached to the ribcage
NO
242
What is pleural fluid
it is secreted by both pleural layers and acts to lubricate their surfaces and creates surface tension that helps maintain the position of the lungs against the thoracic wall
243
what is atmospheric pressure
the pressure exerted by the weight of the gas in the atmosphere on objects on the Earth's surface (760 mm Hg at sea level)
244
what is intra alveolar pressure
the pressure w/in the alveoli (when equal to atmospheric pressure it is 760 mm Hg)
245
what is intrapleural pressure
the pressure w/in the pleural sac that is exerted outside the lungs w/in the pleural cavity, typically less that atmospheric pressure
246
what is the purpose of the pleural cavity producing a negative pressure
it allows the lung to slide along the ribcage but does not allow them to be pulled from the ribcage
247
what does surface tension of the pleural fluid provide
cohesion between the lung and the thoracic wall
248
what allows the lung to maintain the correct amount of pleural fluid in the lung
the continual removal of excess pleural fluid
249
what happens if there is too much fluid in the pleural cavity
a collapsed lung
250
what can cause an accumulation of air in the pleural cavity
chest injury, lung disease, ruptured air blisters, and mechanical ventilation
251
what is the relationship between BP and BV
the smaller the BV the higher the BP
252
what is plumonary ventilation (breathing)
inspiration and expiration
253
what is external respiration
gas exchange between alveolar capillaries and the alveoli
254
what is internal respiration
oxygen movement from blood into tissues; carbon dioxide from tissues into the blood
255
what is pressure
gas molecules exerting force on surfaces w/ which they contact
256
how do gasses normally present themselves
as a mixture of different types of gases
257
what is partial pressure
the pressure of a single gas w/in a mixture of gases
258
what is Dalton's law
the total pressure of an ideal gas mixture is the sum of the partial pressures of the gases in the mixture
259
what are the three gases typically found in a mixture
N2, O2, and CO2
260
where does a gas typically move to
an area with a lower partial pressure
261
what is the partial pressure for O2
158.8 mm Hg
262
what is the partial pressure for CO2
.3
263
what is alveolar air
the compostion and partial pressure of air in the alveoli
264
what is the partial pressure of O2 in the alveoli
104 mm Hg
265
what is the partial pressure of CO2 in the alveoli
40 mm Hg
266
what is involved in inspiration
contraction of skeletal muscles (inhale)
267
what is involved in expiration
the relaxation of skeletal muscle (exhale)
268
what are the two muscle groups used during normal inspiration
diaphragm and the external intercostal muscles
269
what are the accessory muscles of inspiration (forceful inspiration)
sternocleidomastoid and scalenus
270
what are the muscles used during active expiration
internal intercostal muscles and the abdominal muscles
271
are the lungs themselves involved with creating the movement that helps inspiration and expiration
no
272
what controls respiration in the nervous system
the respiratory center
273
how are the neural impulses sent from the respiratory center to the diaphragm
phrenic nerves
274
what is the pre-Botzinger complex
a group of pacemaker neurons that spontaneously depolarize, initiate action potentials, and repolarize in a rhythmic fashion establishing respiratory rate
275
where is the respiratory center located in the brain
the medulla and the pons region
276
what groups are located in the medulla
the ventral respiratory group and the dorsal respiratory group
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what groups are located in the pons region
pneumotaxic and apneustic center
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where is the pre-Botzinger complex located
directly above the ventral respiratory group
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what is the dorsal respiratory group (DRG)
it sends efferent signals to maintain to constant breathing rhythm by stimulating the diaphragm and intercostal muscles to contract, the neurons continue to produce action potentials even in the absence of external afferent signals, as well as influenced by afferent inputs from stretch receptors and chemoreceptors
280
what is the ventral respiratory group
it contains both inspiratory and expiratory neurons that primarily become active during excercise and stress which is involved w/ force breathing
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what are the pontine respiratory groups responsible for
regulating the rate of breathing (pneumotaxic) and the duration of inspiration (apneustic) as well as regulating the DRG neurons
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what are the two things that can stimulate the medulla influencing the respiratory rate
PCO2 and pH
283
what are central chemoreceptors
they are medullary cells responsible for monitoring CO2
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how do the central chemoreceptors respond to elevated CO2 levels
the respiratory centers stimulate an increase in respiration rate to expel more CO2 by responding w/ an increase in H+
285
what are peripheral chemoreceptors
they are specialized receptors located in the carotid arteries and the aortic arch that are made to increases afferent signals to the respiratory centers in response to a decrease in pH and oxygen as well as an increase in CO2 (partial pressure)
286
because the body doesn't compensate for a decrease in PaO2 (monitored by the carotid bodies) until it falls well below normal what is assumed
under normal circumstances oxygen plays no role in the stimulation to breath
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what other signals can alter breathing
increase production of lactic acid, arterial H+, and alveolar ventilation and the stimulation of peripheral chemoreceptors and medullary inspiration neurons
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what is a heme
the prosthetic group (non-amino part) in hemoglobin
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how many oxygen atoms can each hemoglobin hold
4 one for each heme
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what is HbO2
oxyhemoglobin
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what is HbCO2
carbaminohemoglobin
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what is HHb
reduced hemoglobin
293
what are the two states hemoglobin can exist in
relaxed (R) and tense (T)
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what is the difference between the two hemoglobin states
the amount of affinity to oxygen respectively
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what percentage of blood from a sample of arterial blood is HbO2
98.5%
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what is cooperativity
as each molecule of oxygen is bound it further facilitates the binding of the next molecule, until all four heme sites are occupied by oxygen
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what are the three major mechanisms that can transport CO2 into a RBC
CO2 is dissolved in the blood plasma, CO2 is transported in th eform of HCO3- (bicarbonate) which also dissolves in the plasma, and CO2 is transported by erythocytes
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what is Le Chatelier's principle
if a stress is placed on a system at equilibrium, the system will proceed in a direction that minimizes the stress such as concentration, pressure, and temperature
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describe Chloride shift
CO2 moves down the concentration gradient dissolving into the RBC binding to the hemoglobin the CO2 quickly turns into Carbonic acid which gets pushed out of the RBC as chloride is pushed in this causes the pH of the RBC to decrease allowing the oxygen to unbind from hemoglobin releasing it from the cell
300
what is the Bohr effect
H+ binds to the Heme group that decreases the binding of oxygen when H+ is elevated
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what is the carbamino effect
the decrease in the affinity of Hb for oxygen in the presence of CO2 NOT THE BINDING OF CO2 TO A HEME PORTION
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what happens to CO2 once oxygen is bound to hemoglobin
the binding releases CO2 and H+ dissociating CO2 from the RBC
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what is Haidane Effect
displacement of CO2 w/ high O2
304
what does low oxygen in tissues do to O2 dissociation from hemoglobin
it improves it
305
what does low pH in tissues do to O2 dissociation from hemoglobin
it improves it
306
what does high pH in tissues do to O2 dissociation from hemoglobin
it reduces it
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what does low PO2 and low pH/high PCO2 increase
the off loading of oxygen in the vicinity of actively metabolizing tissues
