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58 Cards in this Set
- Front
- Back
what does external respirtion involve? |
exhange of O2 and CO2 with the environment |
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What does internal respiration involve? |
cellular respiration (uptake of O2 and production of CO2 in individual cells) |
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what three processes are involved in external respiration ? |
1.Pulmonary ventilation (breathing) |
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what is pulmonary ventilation? what does it provide |
-the physical movement of air in and out of respiratory tract -provides alveolar ventilation |
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what does the movement of air dependent upon |
atmospheric pressure |
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what muscle do the lungs rest upon? |
the diaphragm |
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what happens to the muscles of respiration as one inhales/ inspiration |
contractions of the diaphragm are combined with contractions of muscles associated with an elevation of the ribs. ( intercostal muscles)
during inspiration the external intercostals (lift ribs up and out) , pectoralis minor (lifts ribs), and sternocleidomastoid ( lifts sternum up and out) muscles contract to expand the rib cage, and the diaphragm |
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what happens during expiration ? |
the muscles associated with expiration relax ( no energy needed) and the elastic properties of the lung sallow them to return back to the resting volume |
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what is required for there to be a flow of air ? |
For air toflowinandoutofthelungs,therehastobeanassociatedpressure difference between theinterna lenvironment of the lungs and the external environment |
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flow of rate equation |
F=(P1-P2)/R
P1=the pressure at point P1 |
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what law is used to describe the pressure in the alveoli and what does it state ? |
Boyle's law: ‘the absolute pressure exerted by a given mass of a confined ideal gas is inversely proportional to the volume it occupies,provided the temperature remains constant’
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Boyle's law equation |
P=1/V or PV=constant
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Boyle's law combined with charles' law |
P = nRT/ V
P=Pressure |
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describe the fow of air |
–Air flows from area of higher pressure to area of lower pressure |
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what does a respiratory cycle consist of ? |
–An inspiration(inhalation) |
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what causes volume changes that create changes in pressure |
Pulmonary Ventilation |
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how does the volume of the thoracic cavity change? |
With expansion or contraction of diaphragm or rib cage |
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what is tidal volume (V T ( T sub)) |
Amount of air moved in and out of lungs in a single respiratory cycle |
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what operates the respiratory pump? What does it aid in ? |
-Cyclical changes in intrapleural pressure operate the respiratory pump. -aids in venous return to heart |
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what happens to the diaphragm and thoracic cavity volume as the rib cage is elevated |
- diaphragm is depressed -thoracic cavity volume increases |
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what happens to the pressures inside and outside of the lungs during inhalation |
Elevation of the rib cage and contraction of the diaphragm increase the size of the thoracic cavity. Pressure within the thoracic cavity |
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what happens to the pressures inside and outside of the lungs during exhalation |
When the rib cage returns to its original position and the diaphragm relaxes, the volume of the thoracic cavity decreases. Pressure rises, and air moves out of the lungs |
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what are the 2 possible causes for lung collapse ? |
(1)Elastic recoil: this is based upon the elastic properties of the alveolar walls. |
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how is the collapse of lungs usually prevented ? |
by a combination of surfactant and intrapleural pressure |
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what is surfactant |
a substance that stops alveoli rubbing together and thus collapse. |
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what secretes sufactant in the lungs and what does it consist of |
Surfactant is secreted by the alveolar epithelium and consists of a mixture of lipoproteins.With surfactant,the attractive force produced by surface tension is about 4 mmHg.Without surfactant,this force would be between 20-30mmHg. |
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how does intrapleural pressure help reduce lung collapse |
During expiration,the intrapleural pressure will drop to about 2mmHg below atmospheric pressure (Atmosphericpressure=760mmHg). |
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what is compliance |
ability to expand (lungs and thorax |
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what kind compliance requires greater force |
low compliance |
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what kind of force is required by high compliance |
low force |
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what are the factors that affect compliance |
•Connective tissue structure of the lungs |
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how is compliance measured ? |
•Thisismeasuredintermsoftheincreasedlungvolumeperunitofpressurechangeinintrapulmonarypressure. |
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what is 1 atm |
760 mmhg |
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describe Intrapulmonary pressure (intra-alveolar pressure) |
–Relative to atmospheric pressure |
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describe maximum intrapulmonary pressure ? |
–Maximum straining, a dangerous activity, can increase range |
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describe intrapleural pressure |
–Pressure in space between parietal and visceral pleura |
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what's pneumothorax |
air into pleural cavuty |
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what is atelectasis |
lung collapse (due to pneumothorax) |
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what is millimetres of mercuryy |
most common weight of reposrting blood pressure and gas pressures |
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what is the mmgh equivalant for 1 torr |
1 mmgh 1 atm r= 760 torr
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atm p at sea level |
15 psi |
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Pounds per square inch |
a measure compressed gas cylinders |
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centimetres of water (cm H2O) |
unit used in hospital for anaesthetic gas pressure and osgen |
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when are accessory repiratory muscles used |
when respiration increases significantly |
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most important muscles of respiration |
external intercostals and diaphragm |
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which type of respiration is passive or active |
exhalation |
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why is exhalation sometimes active |
when it is forced |
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muscles used in inhalation |
–Diaphragm |
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muscles used in exhalation |
–Internal intercostal and transversus thoracis muscles |
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accessory muscles of inhalation |
-Sternocleidomastoid |
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accessory muscles of exhalation |
- internal intercostals -transeversus thoracis - external oblique -internal oblique -rectus abdominis |
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primary muscle of inhalation |
diaphragm external intercostals |
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what's quiet breathing |
Involves active inhalation and passive exhalation |
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what dominates deep breathing |
diaphragm/ diaphragmatic breathing |
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what muscle dominated shallow breathing |
rib cage ( costal breathing ) |
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describe forced breathing (hyperapnea) |
–Involves active inhalation and exhalation |
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what happens to the intrapulmonary pressure when the intrapulmonary volume changes |
it also changes |
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expansion of thoraci cavity does what to the volume |
increases it (pressure decreases so gas now flows from outside to inside) |