| what are xerophytes | adapted living in areas where their water losses due to transpiratation. |
| xerophyte adapatations (cuticle) | thick cuticle - the thicker it is, the less water vapour can escape by this means. reduce water vapour loss |
| xerophyte adapatations (curling up leaves) | most leaves have their stomatota located on the lower epidermis. The curling of leaves in a way protects this lower epidermis from the outside helps to trap a region of still air within the curled leaf. this region becomes saturated with water vapour and so there is only a very slight water potential gradient between the sub stomatal air space and outside, so transpiration is reduced. |
| xerophyte adapatations (having tricohomes (hairs) on leaves) | traps moist air next to the leaf surface. the water potential gradfient between the inside and the outside of the leaves is reduced and therefore less water vapour is lost by transpiration |
| xerophyte adapatations (having stomata in pits or grooves_ | these trap moist air next to the leaf and reduce the water potential gradient |
| xerophyte adapatations (having sunken stomata) | the stomata are located just below the surface of the epidermis, so they are not exposed to air movements |
| xerophyte adapatations (having needle like leaves) | the rate of water loss can be reduced. this reduction is surface area must always be balances againsit the need for a sufficient area for photosynthesis to meet the needs of the plant |
| xerophyte adapatations (closing stomata when transpiration rates are very high) | close hottest part oif teh day. |
| xerophyte adapatations (multi layerd epidermis) | reduces water loss through the cuticle because this increased the distance for diffusion of water vapour from the intercellular air spaces. known as hypodermis. |
