b3.1--gas exchange Flashcards
ventillation
a system for brining atmospheric air (containing 02) into our lungs and expelling waste gases (mainly CO2) from our bodies
gas exchange
a system to bring the O2 from the atmospheric air into the blood and put the CO2 from our blood into the waste gasses in our lungs
surface area
must be large enough to absorb O2
cell volume
how much oxygen is needed and how much CO2 is produced
surface area volume ratio
determinant of cell size
properties of gas exchange surfaces
- thin 2. moist 3. large SA
diffusion
the movement of particles from an area of high concentration to an area of low concentration
inhaling /6
- air enters 2. external intercostal muscles contract (rib cage up and out) 3. diaphram contracts–becoming flatter 4. volume of thorax increases 5. lung pressure lowers relative to air pressure 6. air is pulled in
spirometer
device used to measure lung ventilation volumes
tidal volume
the normal volume of air displaced between normal inhalation and exhalation when extra effort is not applied
inspiratory reserve volume
the amount of air that can be forcibly inhaled after a normal breath
expiratory reserve volume
the amount of air that can be forcibly exhaled after a normal breath
vital capacity
the maximum amount of air that can be exhaled
transpiration
evaporation of water through the stomae
factors that affect transpiration
increase transpiration: light intensity, temperature, wind speed. decrease transpiration; humidity
stomal density
of stomaes divided by the area of the field of view
