Heathland: Banksia - Lower Surface of Leaf (SEM)
What function might the epidermal hairs serve? Select the best response.
Heat retention in winter
Protection from browsing
Trap a layer of humid air
try again
NSome plants in very cold climates have hairy leaves, but the hairs can't keep the leaves warm, since leaves don't generate internal heat. Try again.
While hairs do deter animals from feeding on leaves, note the location of the hairs. There is another function.
Yes! The hairs have the effect of trapping a layer of humid air in the vicinity of the stomata, and this so-called boundary layer of humid air minimises the rate of evaporation from the stomata.
Well done, you answered correctly. Use the 'next' button to proceed.
Banksia leaves are usually tough, dorsiventral and have toothed margins. This is a scanning electron micrograph (SEM) of the underside of a banksia leaf. The magnification is approximately 1000X.