Topic 7 Respiratory_3 Flashcards
Blood supply to the lungs - process
Alveoli are surrounded by capillaries
> gas exchanges happen through simple diffusion across the alveolar and capillary walls (respiratory membrane)
> oxygen from the air into the blood (inhale)
> carbon dioxide from the blood into the air (exhale)
What forms the respiratory membrane?
Alveolar & capillary walls
> alveolar epithelium
> basement membrane underlying alveolar epithelium
> basement membrane underlying endothelium, endothelium
Gas transport happens via 2 ways?
Oxygen
Carbon dioxide
What type of gas is carried from the lungs to the body tissue bound to hemoglobin (Hb)?
> a little is dissolved in the body
> it goes to the body tissues and is used
Oxygen
What type of gas is carried in the blood in the from of bicarbonate (HCO2)?
> some is carried attached to Hemoglobin
> a little is dissolved in the blood
> it is released at the lungs and exhaled
Carbon dioxide
** some is carried attached to Hb (carboxyhemoglobin)
Each lung is enclosed in, and protected by a double layered serous membrane - what is it called?
Pleural membrane
The layer of Pleural membrane that covers the lungs
Visceral pleura
The layer of Pleural membrane that covers the inside of the thoracic cavity
Parietal pleura
The space b/w the visceral & parietal pleura which contains the lubricating fluid
Pleural cavity
Type of Ventilation... Active process - mm contractions expand the lungs and thoracic cage Thoracic volume increases Thoracic pressure decreases Air rushes in to normalize the pressure
Inhalation
Type of Ventilation... A passive process (when at rest) Muscle relax, elastic recoil of the thoracic cage Thoracic volume decreases Thoracic pressure increases Air rushes out to normalize the pressure
Exhalation
Term
The largest volume of air that can be brought into the lungs
Forced Vital Capacity (FVC)
** maximum inhalation
Term
The volume of air that can be exhaled in 1 second (after maximum inhalation)
Forced Expiration Volume (FEV1)
Term
The volume of air in one regular breath
Tidal volume (Vt) ** regular resting breath (sitting)
Respiratory system control via 2 means
Central control
Peripheral chemoreceptors
Type of respiratory control centre..
The respiratory control centre (in the brain stem (pons & medulla oblongata)) control the rhythm and rate of breathing
> Central chemoreceptors detect rising concentrations of CO2 and H+ and respond by increasing ventilation
Central control
*relates to Negative feedback loop
Type of respiratory control…
Located in the carotid arteries and the arch of the aorta
They respond to rising CO2 and H+(hydrogen) concentrations and/or dropping O2 (oxygen) concentrations and respond by increasing ventilation
Peripheral chemoreceptors
