Biology: Xerophytes Flashcards
What are Xerophytes?
highly adapted plants to prevent water loss when stomata are open
Why is a small leaf an important adaptation?
reduced surface area for evaporation
Why is sunken stomata an important adaptation in Xerophytes?
maintains humid air around stomata to reduce water potential gradient
Why are stomatal hairs an important adaptation in Xerophytes?
maintains humid air around stomata to reduce evaporation and water potential
Why are rolled leaves an important adaptation to Xerophytes?
reduces effect of wind to reduce water potential and evaporation
Why are extensive root systems an important adaptation in Xerophytes?
maximises water uptake / wide area to absorb rainfall / swollen stems to store collected water
Outline the structure of a dicotyledonous
stomata on lower side, net-like veins, palisade and spongy mesophyll
Outline the structure of monocotyledon
stomata upper and lower side of leaf, veins run parallel to one another
Why is a reduced number of stomata an important adaptation in Xerophytes?
reduce places water can evaporate from
Why is a thicker, waxy cuticle an adaptation in Xerophytes?
waterproofs leaves and stems to reduce evaporation
How can we investigate stomatal density?
-examining thin layers of epidermis or ‘imprints’ of leaf
-multiple sections calculated to determine a mean
-can be scaled to whole leaf
