respiratory system Flashcards
what is the Bohr effect
right shift in oxy hemaglobi dissociation curve
- decrease in pH
- increase in Co2
- increase in temp
what does oxytocin’s haemoglobin dissociation curve represents
saturation of haemoglobin with oxygen at various CO2 levels
at rest what is the O2 content of the atrial blood
20 ml of O2 per 100 ml blood,
this’ll be 15 ml when blood passes through capillaries into the venous system and returns to the heart
what is arterial mixed venous oxygen difference
the difference between arterial and venous blood ( the amount of oxygen is extracted from the tissues )
what is an internal respiration
the exchange of the gases at cellular level ( blood and skeletal muscles ), net diffusion from low to high until equilibrium is reached
what is an external respiration
movement of the gases at the alveolar- pulmonary capillary level
- oxygen moves from alveoli into pulmonary capillaries
- CO 2 from pulmonary capillaries to alveoli
what are the levels of of oxygen and CO2 at external regulation
oxygen is low
co2 is high
what does movement of gases between the alveoli, cells and blood depend on
on partial pressure difference of gas across the regions
what is partial pressure
pressure that is exerted from a single gas
what is Dalton’s law
partial pressure is directly proportional to the percentage of the gas in the mixture
what is a barometric pressure
the total gas pressure, 760 of atmosphere
what is the blood flow to the lung at rest
low pressure and resistance in pulmonary system compared to system circulation
-uneven distribution of blood to lungs
formula for minute ventilation
breathing rate x tidal volume
define tidal volume
volume of air that moves in and out of the lungs with each breath ( 500)
define inspiratory reserve volume
air that can be insides forcible beyond the tidal volume ( 2100- 3200)
define expiratory reserve volume
air that can be evacuated from the lungs after a tidal expiration ( 1000-1200)
define residual volume
air left in the lungs after strenuous expiration ( 1000)
what happens during inspiration
diaphragm moves 1 cm and ribs lifted by muscles
intra- thoracic presser fall and 2-3 laters inhaled
what happens during expiration
- passive process with no muscle movement
- elastic recoil and surface tension in alveoli pulls inwards
- alveoral pressure increases and air pushed out
forced expiration
abdominal muscle force diaphragm up
internal intercostals depress ribs
forced inspiration
minor lift chest upwards
tell components of conducting zone
nose pharynx larynx trachea bronchia and bronchial tree
tell commonest of respiratory zone
bronchioles
alveolar ducts
alveoli
tell what is Fick equation
VO2= stroke volume x HR x a-vO2 difference
