partial pressures and mechanisms of ventilations

what are the functions of the lung

• allow exchange of oxygen between inspired air and blood

• help regulate acid base balance

• play a role in metabolism of substances

• allow elimination of co2

what is the atmospheric pressure or P_B

760 mmhg

how does gas move from alveolus to blood

diffusion

what method of gas movement is independent of composition of gas

bulk flow

what method of gas movement is dependent on composition of gas

diffusion

what is the normal P_AO2

105 mmhg

why is P_AO2 105 mmhg when oxygen is 21% of the barometric pressure

because of water vapor and left over co2 already present in the alveolus

what is a normal P_aO2

80-100 mmhg

what would cause an increase in P_AO2

decreased metabolic rate

When metabolic rate is decreased less oxygen is utilized meaning less needs to be taken from the alveolus and given to the blood which _______ P_AO2

increases

what would increase P_ACO2

• decreases alveolar ventilation

• increased metabolism

• decreased cardiac output

at rest a dogs interpleural pressure is usually ________

negative

the negative interpleural pressure prevents the alveolus from expanding, but to prevent it from collapsing the transpulmonary pressure exerted is equal and ________ to the interpleural pressure

opposite

Transpulmonary pressure is equal to what

P_A- P_IP

as you breathe in your thoracic volume increases which leads you intrapleural pressure to _________

decrease

Once intrapleural pressure decreases what increases

Transpulmonary pressure

transpulmonary pressure and _______ are positively corelated

volume

label the graph of lung volumes

a. inspiratory reserve volume

b. tidal volume

c. expiratory reserve volume

d. residual volume

e. inspiratory capacity

f. functional residual capacity

g. vital capacity

h. total lung capacity

the amount of air that enters and exits the lung on a normal breath would be called the _______

Tidal volume(V_T)

the maximum amount of extra air you can inhale after a normal breath is called what

inspiratory reserve volume

the maximum amount of extra air you can exhale after a normal breath out is called what

expiratory reserve volume

the air left over in the lung after breathing out all possible is called the what

residual volume

air left in the lungs after a normal breath out is called the what

functional residual capacity

the max amount of air a person can inhale is called the

inspiratory capacity

the maximum a person can exhale after an maximum inhalation is called the what

vital capacity