Question

plants absorb water from their roots,,,,,,,,,,,,but how water goes from roots to plant if a gravitational force is acting on it?????????????????????

Answer 1

It is going through diffusion. in short trees it is takes place with the help of root pressure and in tall trees it is occur with the help of transpiration pull

Answer 2

Plants absorb water from their roots , and the ascent of sap takes place by the process of Active tranport,where the water is sent frm a region of low concentration to high concentration by expenditure of energy.

In taller plants, the transpirational pull helps in doin so.The process of transpiration helps in the ascent of sapby producing a suction force acting from the top of the plant.Evaporation fron the leaves concentrates the sap and increases its osmotic pressure and a suction force is created at the top of the plant, drawing more water through the stem and making the roots absorb more of  them

Some other factors which take part are adhesion,cohesion,Root pressure and the narrow diameter of the xylem tube