why do plants carry out homeostasis
to maintain a constant internal environment
what is the function of stomata / guard cells
to control the diffusion of gases (carbon dioxide) in and out of leaves
what are the environmental stimuli that cause stomata to open
increasing light intensity
low CO2 concentrations in the air
what are the environmental stimuli that cause stomata to close
darkness
high CO2 concentrations in the air
low humidity
high temperatures
water stress
what is the use of regulating stomatal aperture
it balances the need for carbon dioxide uptake by diffusion with the need to minimise water loss by transpiration
advantage of stomata being open during the day
leaves gain CO2 for photosynthesis
advantage of stomata closed during the day
water is retained inside the leaf which is important in times of water stress
disadvantage of stomata open during the day
leaves lose large amounts of water by transpiration
disadvantage of stomata closed during the day
supply of CO2 decreases and so does the rate of photosynthesis
stomata open and close in what routine
a daily rhythm
true or false
the daily rhythm of stomatal opening and closure is affected by light intensity
false
nothing affects the rhythm
what is the purpose of opening stomata during the day
maintains the inward diffusion of CO2 and the outward diffusion of oxygen
allows the outward diffusion of water vapour in transpiration
what is the purpose of closing stomata at night
reduces the rate of transpiration
conserves water