This is a one paged summary on xerophytes! (plants which have adapted to live in conditions without much water).

Hope it helps ;D

HideShow resource information
Preview of Xerophytes

First 300 words of the document:

Some plants which live in hot and dry places where their water intake is less than their
water outtake have adapted to suit these problems. Since water is lost mostly by
transpiration, factors which affect the rate of transpiration have been adjusted and
changed to minimize water loss. Since leaves lose the water, this is where the most
adaptations have been shown:
A thick cuticle; to stop water from evaporating out of plants, they've developed a
thick, waxy, waterproof cuticle which doesn't allow the water out as much as
normal cuticles
Rolling up of leaves; since the stomata are mostly located in the lower epidermis
which is on the underside of the leaf, when the leaf is folded, it traps still air.
Water can collect here, therefore there's no water potential gradient between the
stomata and the air, so water can't evaporate out
Hairy leaves; the hairiness of
some leaves mean that water is trapped on the tiny hairs, reducing the water
potential gradient, limiting water loss yet again
Stomata in pits or grooves; the stomata been located in pits or grooves in a
plant means that water is collected in these pits, again reducing the WP gradient,
meaning transpiration is harder to carry out
Reduced surface area to volume ratio of the leaves; we know that low surface
area to volume ratio means that materials are harder to diffuse and get to cells,
this also means that water is harder to evaporate and transpire from cells.
Although this conflicts with the need to photosynthesise, so the leaves are
usually short and rounded and in spike form (like cactus's)


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all resources »