Physiology with Pharmacology Respiratory Revision
0.0 / 5
- Created by: Sarah
- Created on: 13-03-17 15:21
What does the conducting zone consist of?
nose, nasopharynx, laryx, pharynx, oropharynx, trachea and bronchial tree
1 of 263
what is the function of the conducting zone?
Filter, warm, humidify
2 of 263
what does the air blood barrier do (near alveoli)?
fas gas exchange to take place multiple barriers, large SA froe xchange
3 of 263
what is the air blood barrier madeup of?
flattened cytoplasm of type 1 pneumuocyte and the capillary wall
4 of 263
what is compliance?
1) measure of elasticity 2) distensibility 3) ease with which lungs + thorax expand with pressure changes
5 of 263
what are the 2 types of dead space?
anatomical (vol of conducting airways at rest 30%) and physiological (vol of lungs not in gas exchange)
6 of 263
what is surfactant produced by?
Type II pneumocytes
7 of 263
what does surfactant do?
stops smaller alveoli collapsing, acts to reduce the surface tension
8 of 263
what disease shows low compliance therefore more work to inspire?
pulmonary fibrosis (paranchyma more rigid)
9 of 263
how do you diagnose restrictive lung disease?
patients vital capacity is reduced below expected for height, age and sex
10 of 263
where are alveoli fed from?
terminal bronchiole
11 of 263
what does Ach do bronchial SM when it binds to muscarinic receptors? (parasympa)
Constricts
12 of 263
Air movement follows Boyle's law, what is this?
The increase in volume leads to a reduction in pressure. Air moves into lungs down pressure gradient
13 of 263
what secondary muscles are used in forced inspiration?
sternacleidomastoids, scalenes, neck+back muscles and upper respiratory tract muscles
14 of 263
in quiet expiration what primary muscles are used?
None! its a passive process so only uses elastic recoul
15 of 263
what disease shows high compliance + more difficulty expiring due to loss of elastic recoul?
emphysema
16 of 263
what are the 2 major components to the elastic recoil of the lungs?
anatomical component (elastic nature of cells + ECM) and surface tension generates elastic recoul at air-fluid interface
17 of 263
what do bronchioles (less than 1mm) have a lack of? what do they have more of?
lack cartilage support, more smooth muscle
18 of 263
what is the equation for compliance?
change in volume/change in pressure
19 of 263
what is the impact of resistance on flow determined by?
Poisuille's law
20 of 263
What does Poiseuille's law state?
airway resistance is proportional to gas viscosity + length of tube but inversely proportional to the 4th power of the radius
21 of 263
how much percentage airway resistance do is given by the pharynx-larynx?
40%
22 of 263
what are factors that affect airway resistance? (all affect airway diameter)
increased mucus, oedma swelling and narrowing, airway collapse eg in forced expiration
23 of 263
how does the parasympathetic autonomic nervous system control bronchial smooth muscle?
Ach release from vagus acts on muscarinic = consstrition
24 of 263
what factors cause the haemoglobin dissociation curve to shift right?
increased temp, Co2, production of and decreased in PH
25 of 263
what are humoral factors affecting control of bronchial SM?
epinephrine- dilation, histamine inflammatory- constriction
26 of 263
what are 2 factors ventilation is affected by?
gravity and posture
27 of 263
what law determines concentration of a gas dissolved in a solution?
Henry's law
28 of 263
name the 5 ways Co2 is carried in the blood?
1) carboic acid 2) carbonate 3) bicarbonate 4) dissolved Co2 5) carbamino compounds
29 of 263
what does restrictive lung disease mean?
reduction in lung expansion
30 of 263
what do both obstructive and restrictive lung disease both do?
reduce ventilation
31 of 263
in obstructive lung disease the spirometer shows a decrease n what?
a decrease in FEV1
32 of 263
what are the obstructive diseases?
asthma, chronic bronchitis, COPD, emphysema
33 of 263
what are the brown inhalers for asthma consist of?
inhaled steroids, glucocorticoids such as beclomestasone
34 of 263
what is decreased on the spirometer for restritive lung diseases?
Vital capacity
35 of 263
what does the apneustic and pneumotaxic centre in the pons do?
send stimuli to medulla about rate and depth of breathing
36 of 263
what does the apneustic centre do?
increases depth, reduces rate. By prolonging inspirations. stimulates ic
37 of 263
what is the name of the reflex where stretch receptors in the lung send signals to medulla to limit inspiration+prevent over inflation?
Hering-Breur reflex
38 of 263
what nerve is used in the Hering Breuer reflex to send info from stretch rec to inspiratory centre?
Vagus nerve
39 of 263
what does the dorsal respiratory group do?
controls inspiration by sending signals to the inspiratory muscles, bouts of activity
40 of 263
how do you diagnose obstructive lung disease?
patients FEV1 is reduced to less han 80% of the FVC
41 of 263
what is the molecualr weight of hameoglobin?
68kD
42 of 263
what enzyme helps convert FE3+ to FE2+?
methaemoglobin reductase
43 of 263
what are the 2 states of haemoglobin?
tense and relaxed state
44 of 263
what does fetal Hb do to the dissociation curve?
shifts it leftwards as there's a higher affinity for O2
45 of 263
what is Daltons law?
the total pressure of a mixture of gases is the sum of their individual partial pressures
46 of 263
what is the composition of air- dry and wet standard atmospheric pressure?
760mmHg
47 of 263
what are ventilation/perfusion mismatches used for?
can be used to determine whether there's a problem with gas ventilation or blood perfusion to that region of the lung
48 of 263
what is the ratio of alveolar ventilation and pulmonary blood flow used to get an idea of?
an idea of the efficiency of gas exchange in particular regions of the lungs
49 of 263
What does the pleura do?
prevents the lungs sticking to the chest wall and enables free expansion+collapse of lungs
50 of 263
what relaxes during quiet expiration?
the diaphragm and external intercostal muscles
51 of 263
what does respirartory epithelium contain?
ciliated epithelium, goblet cells and sensory nerve endings
52 of 263
what is internal respiration?
respiration withing the cell eg glycolysis krebs
53 of 263
what is external respiration?
ventilation,exchange and transport of gases round the body
54 of 263
if the distance of diffusion is longer what does this do the time taken to equilibrate?
longer to equilibrate as further to go
55 of 263
what does the pulmonary circulation carry blood to zand from?
between the heart and the lungs, carries deoxygenated blood from heart to lungs back to heart
56 of 263
what are the 2 branches the lung is divided into?
conducting zone and resporatory zone
57 of 263
what happens in respiratory zone?
is where gas exchange takes place
58 of 263
what is the conducting zone
pathway gas to and from respiratory zone
59 of 263
main features of structure of bronchial wall?
elastic tissue, cartilage, smooth muscle, mucous glands
60 of 263
what are bronchioles linked by?
respiratory epithelium
61 of 263
what do bronchioles have proportionately more of?
smooth muscle
62 of 263
how are alveoli adapted?
large sa for gas exchange, thin walled short diffusion distanceq
63 of 263
what is the air blood barrier made up of?
cytoplasm of type 1 flattened pneumocytes and capillary wall
64 of 263
what other cells are found at the air blood barrier?
macrophages and fibroblasts
65 of 263
what are the 2 processes of ventilation?
inspiration and expiration
66 of 263
in what pressure gradient does air move into the lungs?
Palv < Patmos
67 of 263
what does quiet inspiration use?
primary muscles of inspiration: diaphragm and external intercostals
68 of 263
what is the effect of the diaphragm and external intercostals in quiet inspiratin?
to increase thoracic and lung volume
69 of 263
what is boyles law?
increase in volume, decrease in pressure air moves down pressue gradient
70 of 263
what happens to the diaphragm and ribcage in inspiration?
diaphragm contracts (moves down) rib muscles contracts (expand)
71 of 263
where does the diaphragm move in expiration?
moves up as it relaxes
72 of 263
what happens to the ribs in expiration?
rib muscles relax (ribcage contracts)
73 of 263
what happens in quiet expiration?
diaphragm relaxes and moves up, relaxation of external intercostal muscles, recoil of lungs (by elastic)
74 of 263
what accesory muscles are used in forced expiration?
accesory muscles, internal intercostals,abdominal muscles and neck and back muscles
75 of 263
what is the pleura cavity filed with?
secretons
76 of 263
from inside out what is the structure of the pleura?
visceral pleura - pleura cavity - parietal pleura
77 of 263
what is happening with the elastic forces in the lungs and chest at rest?
elastic forces equal (in lung and chest)
78 of 263
the intrapleural space is less than atmospheric pressure why?
at rest inward force of elastic of lungs (collapse) and chest wall tends to expand but at rest inward+outward forces balances
79 of 263
what is pneumothorax?
collapsed lung
80 of 263
what is compliance?
measure of distensibility/elasticity or the ease which the lung and thorax expand during presure changes
81 of 263
what is surfactant made of?
lipoprotein- lipids+proteins
82 of 263
what cells make surfact?
type 2 pneumocytes
83 of 263
what does surfactant do?
prevent alveolar collapse, alveolar size regulation, increases compliance (allows lungs to inflate more easily), production decreases (pmneumonia), prevents oedma
84 of 263
why does surfactant control alveolar size regulation?
the rate of inflation is slowed by the spread of surfactant
85 of 263
what happens in pneumonia?
productionof surfactant decreases making the lungs harder to inflate
86 of 263
what does surfactant prevent by stopping fluid entering the alveoli ?
prevents oedma
87 of 263
what overcomes the problem of smaller alveoli collapsing?
surfactant as it reduces the surface tension
88 of 263
what does surfactant do?
reduces he number of water molecules being pulled up to the surface
89 of 263
where is the dorsal respiratory group?
medullary centres
90 of 263
what does the dorsal respiratory group do?
controls inspiration by sending signals to inspiration muscles
91 of 263
what respiratory group shows a spontaenously active period of activity shuts off period of activity?
dorsal
92 of 263
what is the ventral respirtory group for?
controlling inspiration and expiration
93 of 263
when is ventral; respiratory group inactive?
during quiet inspiration
94 of 263
what does the hering breuer reflex prevent?
over inflation of the lungs
95 of 263
where does central chemoreceptors monitor conditions?
in the CSF
96 of 263
what do central chemoreceptor detct?
CO2 and PH
97 of 263
what is the indirect response of the central chemoreceptors to a rise in CO2?
increase in ventilation
98 of 263
where are peripheral chemoreceptors located?
in carotid body and aortic arch
99 of 263
what do peripheral chemoreceptors respond to?
increase in CO2, decrease in pH (more acidic), decrease in O2
100 of 263
what does the phrenic nerve do?
stimulate the diaphragm to contract under the inspiratory centre in the herring breur reflex
101 of 263
what happens in the hering breuer reflex?
stretch receptors in the lung send signals back to the medulla to lmit inspiration
102 of 263
what are the 2 cenres in the pons that send stimuli to the medulla about rate and depth?
pneumotaxic centre, apneustic centre
103 of 263
what effect does the pneumotaxic centre have on the inspiratory centre?
inhibitory
104 of 263
what centre in the pons icnreases rate of breathing by shortening inspirations?
pneumotaxic
105 of 263
what does the apneustic centre do?
dereases rate prolong inspirations
106 of 263
where is the basic respiratory rhytm generated?
centres in the medulla
107 of 263
what kind of process is breathing?
automatic and rhymical
108 of 263
breathing is an involuntary mechanism but can be alered consciously how?
1) hyperventilation 2) holding breath
109 of 263
how is restrictive lung disease diagnosed?
VC is below whats expected for their age
110 of 263
What are obstructive diseases (FEV1 less than 80% of FVC)?
emphysema, chronic obstructive pulmonary disease, asthma, chronic bronchitis persistent productive cough and excess mucus secretion
111 of 263
what is an obstructive lung disease?
reduction in flow through airways
112 of 263
which lung disease obstructive or restrictive reduce ventilation?
both!
113 of 263
what changes in the flow-volume loop in obstructive diseases?
theres a sharp fall in flow rate giving concave shape
114 of 263
what stay similar in flow-vol loops for obstructive diseases?
initial flow and peak flow
115 of 263
what 2 triggers are there for asthma?
1) atopic (etrisic) 2) non-atopic (intrinsic)
116 of 263
what atopic asthma triggers are there?
exrinsic so allergies contact with allergens
117 of 263
what non atopic triggers are there?
intrisic- so respiraory infections, cold air, stress, exercise, inhaled irritants and drugs
118 of 263
what is the response to asthma triggers?
movement of inflammatory cells into the airways, releases inflammatory mediators such as histamine and causes bronchoconstriction
119 of 263
what is an example of a restrictive disease?
asbesrosis
120 of 263
what happens in asbestosis?
slow build up of fibrous tissue leading to loss of compliance
121 of 263
what is there a reduction in on a flow volume loops with restrictive diseases?
reduction in: 1) vols of air moved 2) peak flow
122 of 263
what happens to the volume time curve for restrictive diseases?
reduction in FVC but FEV1 can stay the same or increase
123 of 263
what do you see with restrictive lung disease on a spirometer?
decreased vc
124 of 263
why would you get a reduced chest expansion in restricte lung disease?
chest wall abnormalities, muscle contraction deficiences
125 of 263
what causes loss of compliance (fibrosis) that causes restrictive lung disease?
normal aging process, increase in collagen, exposure to environmental factors
126 of 263
what are longer acting treatments of asthma?
steroid inhalers contianing glucorticoids such as beclometastone refuce inflammatory response, long acting B-adrenroreceptor agonists
127 of 263
what happens in obstructive lung diseases?
the result of narrowing of airways because: excess secretions, inflammation and bronchoconstriction (asthma), all = increased resistance to flow
128 of 263
what does carbon dioxide and water make?
carbonic acid
129 of 263
what can carbnic acid dissociate to?
bicarbonate and hydrogen ions
130 of 263
what is grouped together as total co2?
carbonic acid, bicarbonate, carbamino compounds, dissolved co2 and carbonate
131 of 263
what kind of structure is haemoglobin? (adults)
tetrameric- 2 alpha and 2 beta
132 of 263
what is the molecular weight of haemoglobin?
68kd
133 of 263
what does each unit in hb consist of?
a haem group and a globin chain
134 of 263
what is the haem unit in haemoglobin?
a porphyrin ring containing a single iron atom
135 of 263
what state does the single iron atom in the porphyrin ring in haem unit have to be in?
Fe 2+ state
136 of 263
what enzyme converts Fe3+ to Fe2+?
methaemoglobin reductase
137 of 263
what 2 states does haemoglobin release in?
relaxed and tense state
138 of 263
what affinity does the tense state have for oxygen?
low affinity for oxygen cant fit in hb
139 of 263
how much blood can be dissolved in the plasma? how much do we need?
0.3ml o2 per 100mls, 15ml O2/min but we need 250ml O2/min, 15:250 ratio plasma cant carry!
140 of 263
what is the property of oxygen that means its not good to transport in the plasma?
it has a relatively solubility in saline
141 of 263
what causes a right shift in the disociation curve?
increased temperature, increased co2, increased production of 2,3 DPG and decreased PH
142 of 263
what causes the haemoblogin curve to shift left?
fetal haemoblogin
143 of 263
a right shift in the Hb cuve does what for oxygen?
haemoglobin has a decreased affinity for the oxygen, releases it to the tissues
144 of 263
what is transpulmonary pressure?
pressure across the airways
145 of 263
what happens when you inflate the lungs with saline?
small pressure increase -> large increase in volume, 1st- overcome ST airways pop open when overcome forces and reach max vol, more linear on graph when coming to residual vol
146 of 263
why is there a curved line for volume against transpulmonary pressure?
there is a small delay in overcoming the forces
147 of 263
why does the lungs have elastic recoil?
due to surface tension
148 of 263
what forces equal out on an ar bubble?
pressure inside the air bubble outwards, surface tension inwards on the air bubble
149 of 263
what is residual volume?
volume left in the lungs
150 of 263
how much of the anatomical dead space?
30% of inspired air = 150ml
151 of 263
what gives the vital capaity?
full inspiration max inflate lungs
152 of 263
what is thre total lung capacity made up of?
residual + vital capacity
153 of 263
what is the FEV?
breathe in, breahe out as hard and long as you can take how much expired in 1 sec
154 of 263
what percentage is a health indicator and should be about 70%?
FEV1/VC gives a ratio
155 of 263
what is tidal vol?
breathe in and out at rest
156 of 263
what is vital capacity?
maximum amount of air inhaled and exhaled during a respiratory cycle
157 of 263
what adds up to the vital capacity?
inspitatory reserve + expiratory reserve + tidal vol
158 of 263
what is the residual volume?
the air left in the lungs after max expiration
159 of 263
what is the inspiratory reserve volume?
amount of additional air that can be inhaled in the lungs by deterined effort
160 of 263
what is the total lung capacity made fro?
vital capacity + residual volume
161 of 263
what is the inspiatory capacity?
the amount of air that can be inhaled after the end of normal expiration IC = TV + IRV
162 of 263
what is sum for inspiratory capacity?
tidal vol + inspiratory reserve vol
163 of 263
what is thefunctional residual capacity?
the volume of air left in the lungs after passive expiration
164 of 263
what decreases as tidal vol increases during exercise?
inspiratory reserve and expiratory reserve
165 of 263
how do you calculate the residual volume?
helium dilution technique, take subject end of normal expiration, air chamber small vol, know conc of elium and vol of chamber, breathe in+out, helium diluted, measure conc
166 of 263
what sum do you use to work out residual volume?
C1V1 = C2V2
167 of 263
what law determines the impact of resitance on flow?
Poiseuilles law
168 of 263
what is flow of air into the lungs proportional to?
the pressure gradient
169 of 263
how do you work out the flow of air into the lungs?
V = change in pressure (palveoli- patmos)/ resistance
170 of 263
what is poiseuilles law (resistance on flow)
the airflow is proportional to gas viscosity and the length of tube but inversely proportional to 1/r^4
171 of 263
what does poiseuilles law show?
small changes in diameter have a big impact on resistance therefore flow
172 of 263
where are the 2 places with 40% resistance in the lung?
1) pharynx-larynx(40%) 2) airways > 2mm diameter
173 of 263
what is the resistance of airways < 2mm diameter?
20%
174 of 263
hang on a minute why is larger airways have more resistance than small?
the sum of the large airways add up like in a circuit, sum of series
175 of 263
what is resistance inversely proportional to?
1/r^4
176 of 263
what affects airway diameter?
1) oedma (swell narrowing->increased resistance) 2) mucus secretions(reduce diameter -> increase resistance)3) collapse of airways (narrows airways-> increased resistance)
177 of 263
how does parasympa act on bronchial smooth muscle?
Ach released from vagus nerve -> acts on muscarinic recs -> CONSTRICTION
178 of 263
Whats released in sympa NS?
noradrenaline -> weak agnist = DILATION
179 of 263
What humoral factors affect control of smooth muscle?
adrenaline in blood, better agonist --> dilation, histamine for inflammation -> costriction
180 of 263
where is the intrapleural pressure (greater = more negative) in the lungs? why?
greater intrapleural pressure at apex due to posture + gravity
181 of 263
where is ventilation greater?
at the base compared to the apex
182 of 263
why is ventilation more at the base?
starting vol of alveoli (less?)
183 of 263
what is a low pressure system?
pulmonary circulation
184 of 263
where is perfusion greater, apex or base?
base
185 of 263
why is perfusion greater at base?
posture and gravity
186 of 263
what is greater at base?
perfusion (posture+gravity) + ventilation (starting vol of alveoli)
187 of 263
what is greater at apex?
intrapleural pressure
188 of 263
what is the ventilation/perfusion ratio?
the ratio of alveolar ventilation and pulmonary blood flow
189 of 263
how do you calculate ventilation perfusion ratio?
ratio = volume/ perfusion
190 of 263
what is the ventilation perfusion ratio used for?
to get an idea of efficiency of gas exchange in the lungs
191 of 263
from the apex to base what happens to the vetilation perfusion ratio?
it gets smaller
192 of 263
what do ventilation/perfusion mismatches show?
not enough blood flow/perfusion to that part of long, prob with gas ventilation
193 of 263
what is the overall ventilation perfusion ratio in the lungs?
0.84
194 of 263
what is daltons law?t
the sum of the partial pressure of gases adds up to the total pressure
195 of 263
what gas is there most of in the air?
nitrogen
196 of 263
how much oxygen in dry air?
21% 160mmHg
197 of 263
what law determines the conc of gas dissolved in a substance?
Henry's law
198 of 263
what is the some for gas dissolved in solution?
Gas dissolved = solubility x partial pressure of gas
199 of 263
how much oxygen dissolved in arterial blood?
0.13mM (100mmHg)
200 of 263
how much oxygen in venous blood?
0.03mM/4ommHg
201 of 263
why cant the plasma deliver enough oxygen alone?
oxygen has a relative low solubility in saline
202 of 263
at rest with cardiac output 5000mls/min how much oxygen can the plasma deliver? how much do we need?
15 o2/min, need 250m o2/min
203 of 263
structure of adult haemoglobin?
tetrameric structure- 4 subunits, each unit has a haem group and globin chain, 2 alpha+2 beta chains
204 of 263
what is the molecular weight of Hb?
68kD
205 of 263
what enzyme converts Fe3+ to Fe2+? why?
methaemoglobin reductase, for o2 to bind needs Fe2+ state
206 of 263
what is the haem unit?
a poryphrin ring containing a single iron atom
207 of 263
what two states does oxygen exist in? whats there affnity for O2?
tense state- low affinity, relaxed state- high affinity
208 of 263
what causes a right shift in the Hb curve?
temp, increased co2, increased 2,3 DPG and decrease in PH
209 of 263
what does the right shift in Hb mean?
decreased affinity for oxygen more oxygen released to tissues
210 of 263
what way does the curve shift for fetal haemoglobin? why?
left- higher affinity for o2
211 of 263
why does fetal hb have higher affinity for o2?
has Y chains instead of B
212 of 263
whats the two routes for carbonic acid?
1) co2 + h2O 2) HCO3 + H
213 of 263
what makes up total co2?
dissolved cabon dioxide, carbonic acid, bicarbonate, carbonate, carbamino compounds
214 of 263
what is the bohr effect?
Hb curve shifts right when ph is decreased, co2 competes for active sites, co2 makes blood acidic
215 of 263
hamburger shift- what is it?
Cl- ions come into the RBC, bicarbonate out of RBC
216 of 263
which oxygen molecule finds it hardest to bind to Hb?
the first as switches tense to relaxed state
217 of 263
what shape is the oxygen-Hb dissociation curve?
sigmoidal
218 of 263
what is happening on the curve at low o2 concentrations?
most Hb is in a tense state (not much change in saturation)
219 of 263
whys it important for curve to shift right with higher temps?
o2 comes off Hb, exercise more hear from metabolic reactions need for O2 for meatbolic reactins so more o2 dissociated
220 of 263
whats normal ph of blood at 40mmHg?
7.4
221 of 263
whatdoes 2,3 bisphosphoglycerate do?
binds to beta chain of Hb stops it binding
222 of 263
why can 2,3 bisphosphoglycerate bind to fetal Hb?
it ahs no beta chain
223 of 263
what catalyses co2 to carbonic acid to bicarbonate?
carbonic anhydrase
224 of 263
how much co2 stays in plasma whats the rest converted to?
10% stays plasma, rest coverted to bicarbonate
225 of 263
how does co2 and water cross the RBC membrane/get in?
co2- reeses assocuated glycoprotein, h20-aquaporin1
226 of 263
why is there a local release of protons?
some co2 binds to Hb gives local release of hydrogen ions breakdown of carbonic acid slightly acidic
227 of 263
what is the anion exchanger that lets cl- into rbc and bicarbnate out?
band 3
228 of 263
what happens to the anion exhcanger in the lungs?
anion exchanger is reversed, bicarbonate goes in(converted to co2), chloride out, chloride or hamburger shift
229 of 263
what is the Hering Breuer reflex preventing? how?
overinflataion of the lungs, strectch recs send sigs to the medulla
230 of 263
what is the cycle in hering breurer reflex?
stretch recs -> vagus nerve -> inhibits inspiratory centre -> phrenic nerve -> diaphragm contracts -> stretch recs
231 of 263
what is the central pattern generator?
pre-botzinger complex
232 of 263
what are the integrating centers?
DRH, VRG, pre-botzinger complex, medullaoblongata, pons and also higher brain centrs and limbic syst for emotions
233 of 263
what detects co2 and Ph in the medulla?
medullary chemoreceptors
234 of 263
what do carotid and chemoreceptors affect?
vagus nerve and glossopharyngeal goes up to integrating system
235 of 263
what detects co2 o2 and ph?
aortic and carotid chemoreceptors
236 of 263
what does the VRG control?
inspiration and expiration- during activation helps control forcefl
237 of 263
when is VRG inactive?
during quiet respiration
238 of 263
what happens to activity of the DRG?
spontaneous period of activity ->shuts off --> period of activity
239 of 263
what does the DRG control? how?
inspiration -> sends sigs to inspiratory muscles
240 of 263
where are the DRG + VRG?
medulla
241 of 263
what inhibitory input is there into the DRG?
vagus and glossopharygeal (by aortic+ carotid chemorecs)
242 of 263
what is the output from the DRG?
Diaphragm
243 of 263
what is the output from the VRG?
intercostals, abdominal muscles
244 of 263
what does the apneustic centre do?
increases depth (prolongs inspiration), stimulates inspiratory centre
245 of 263
what inhibits the inspiratory centre?
VRG
246 of 263
what increases thre rate by shortening inspirations?
pneumotaxic centre
247 of 263
stimulation of central or peripheral chemorecs has what effect?
increase in ventilation
248 of 263
what do central chemoreceptors look at?
monitor conditons in CSF, senses CO2 and PH
249 of 263
what do peripheral chemoreceptors respond to?
decrase in o2 or ph, increase in co2
250 of 263
where are peripheral chemorecs?
catotid body and aortic arch
251 of 263
what changes in the flow-vol loop in obstructive diseases?
sharp fall in flow rate
252 of 263
2 key features in restrictive lung diseases?
fall in chest expansion, loss of compliance
253 of 263
3 reasons why you'd get a loss of compliance in restrictive?
1) normal aging 2) increase in collagen 3) exposure to collagen dust
254 of 263
whats the prob with chest expansion in restrictive lung diseases?
chest wall abnormalities and muscle deficiencies
255 of 263
where does the lesion need to be to lose resp rhythm?
below medulla
256 of 263
where does DRG go to?
external intercostals- for quiet inspiration
257 of 263
what does the pons reg?
rate and depth of breathing
258 of 263
2 centres in pons?
pneumotaxic and apneustic
259 of 263
where is the inspiratory centre?
in the medulla
260 of 263
the chemorec primary drive is usually co2 levels but what happens in emphysema?
o2 drive takes over, loss of elastic (cant expel co2) get use to elevated co2 levels, o2 becomes drive for chemorecs
261 of 263
what feeds into the pre-botzinger complex to modulate breathing pattern?
receptros (chemo)
262 of 263
what do VRG + DRG change?
contraction of muscles
263 of 263
Other cards in this set
Card 2
Front
what is the function of the conducting zone?
Back
Filter, warm, humidify
Card 3
Front
what does the air blood barrier do (near alveoli)?
Back
Card 4
Front
what is the air blood barrier madeup of?
Back
Card 5
Front
what is compliance?
Back
Related discussions on The Student Room
Similar Biology resources:
0.0 / 5
0.0 / 5
5.0 / 5 based on 1 rating
0.0 / 5
0.0 / 5
4.0 / 5 based on 1 rating
0.0 / 5
Comments
No comments have yet been made