2points
why do only active margins have trenches?
o
a. trenches are filled with basalt.
o
b. trenches are caused by subduction.
o
c. only passive margins have subduction.
o
d. trenches are caused by erosion.

Basically  transpiration is set up when sunlight hit the surface of the leaf> which causes the leaf to loose water by evaporation. The process of evaporation from the leave surface is called transpiration. certain pores well distributed on both  surfaces of the leaf called stoamta  are the channels fro evaporation of water vapour in leaf.They are also for exchange of Oxygen with Carbodioxide.

As a result  of constant  loss or water from the leaf , the water potential gradient  of the leaf internal layer drops compare to the  surrounding environments. This  decreases through out the plants.  However the water potential  gradient of the surrounding soil is greater than the  the plants inner layer.

Consequently, water moves through the forces of adhesion cohesion, capillarity through the  roots of plants through the xylem tissue  in the stem to  reach the  leaves for transpiration to continue.

The stomata regulate the process of transpiration  by the opening and closing of its  guard cells  guiding  the stoma while the Xylem tissues and trachieds serve as the vascular tissues for  transport of water and minerals  from the roots to the leaves to set -up transpiration

The basic function of transpiration it to cool the plants, because evaporation draws heat from plants to bring about cooling, and to  stimulate water movement through xylem in plants

Explanation: