respiratory system Flashcards
what is the respiratory systems function
to bring in air to the body from the external environment and to expel CO2 waste products from the body.
what is the function of the left/right bronchi
it distributes air
what is the function of tongue
it helps swallow
what is the function of the epiglotis
it ensures food diverts into the oesophagus
what is the larynx
voice box
what is the function of the trachea
it is the wind wipe
what is the function of the left /right lobe
it is the left/right lung
what is the function of the diaphragm
it contracts to put air into the lung
what is the function of the nasal passage
it humidifies
what is the pharynx
the throat
what is the function of the nose
it warms and filters the air before it goes in
what is the breathing anatomy
- the nose filters and warms the air with a mucus membrane and hairs (cilia)
- the pharynx- the throat
- the larynx is the voice box and meets the trachea
- epiglottis ensures that food is diverted into the oesophagus and not the trachea
what happens as the diaphragm contracts
the volume in the lobes increase so pressure decreases so air will move from the external environment where there is higher pressure to the lungs.
where does blood flow the slowest and why is this helpful
blood flows slowest in the capillaries which is helpful for gas exchange so if it wasn’t flowing slow exchanging couldn’t be done properly.
explain the mechanics that support breathing and the importance of a airtight pleural cavity
during inspiration
1. the diaphragm contracts and flattens
2. pleural cavity increases in volume causing pressure inside to lower
3. the pressure exists and goes to a high to low movement
4. air moves into the lungs
during expiration
1. the diaphragm relaxes
2. pleural cavity decreases in volume
causing pressure inside to increase
4. the pressure gradient exists and goes to a high to low movement
5. air moves out of the lungs
intercostal muscles have what
internal is for respiration and external is for inspiration
what do external intercostals do
they pull the ribs together raising the rib cage for inspiration
what is pulmonary ventilation
the process by which ambient air is brought into and exchanged with air in the lungs
what is the size of lung volume
4-6 litres
what is inspiratory reserve volume
following inspiration the amount of air that you could continue to inspire if required
what is vital capacity
the maximum volume forcingly expired following a maximum inspiration
what is expiratory reserve volume
the volume of air that remains in the lungs following expiration
what is tidal volume
the amount of air inspired or expired in 1 breath
what is total lung capacity
the complete volume of air present in the lungs after maximal inspiration
what is minute ventilation
the volume of air inspired or expired per minute
what is residual volume
the amount of air that remains in the lungs after after a maximal expiration
how to work out functional residual capacity
expiratory reserve volume + residual volume
how to work out minute ventillation
tidal volume x breathing rate
how do gases move
- gases exert pressure (mmhg) mercury
-atmospheric air (sea level)
-exert pressure of 760mmhg
what pressure does atmospheric air exert
760mmHg
what is partial pressure
the pressure of a gas within a mixture of gases
for example oxygen is worth 21% of the earths atmosphere so to work out partial pressure you do 21% of 760
decimal x pressure
what is the effect on the partial pressure of oxygen as the air reaches the alveoli
partial pressure reduced from 160mmHg to 105mmHg as it has been mixing with the dirty air from the residual volume and the expiratory resolve volume
diffusion of O2 what is the PO2 in the alveoli and the alveolar capillaries
alveoli- 105mmHg
alveolar capillaries-40mmHg
however pressure attempts to equalise by moving from high to low diffusing across the membrane
the result is that o2 moves from the alveoli into the capillaries
how do you work out the pressure gradient
it’s the different between 2 pressures
diffusion of CO2
what is the pco2 in the alveoli and the alveolar capillaries
alveoli-40mmHg
alveolar capillaries- 45mmHg
the pressures will attempt to equalise moving from high to low diffusing across the membranes.
the result is the CO2 moves from the capillaries into the alveoli
what factors enable efficient diffusion
-slow flow of blood
-thin capillary membrane
-huge surface area
- diffusion gradient
what factors determine the partial pressure of any gas within a mixture of gases
-concentration of the individual gas
-the total air pressure
how does o2 diffuse across the alveolar capillary membrane
-pressure gradient exists
-o2 will move into the capillary
-movement from high to low
-high pressure in alveoli and lower in capillary
what significance does the size of the gradient have upon the speed of diffusion
the greater the gradient the greater the diffusion
what challenges does the body have at altitude, what is the impact of breathing and o2 delivery
-altitude lowers total air pressure therefore PO2 will be lower in the alveoli
-smaller gradient now exists between alveoli and capillary
-this results in a slower diffusion of O2 in to blood and less O2 transfered
