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How does sap rise in a tree
How dows sap rise in a tree?
Nourishment for plants is essential, as much as it is in the case of human beings. All parts of our body are nourished by the blood, pumped constantly by heart. The Trees and plants obtain their nourishment from sap water. Although the trees have no heart to pump the food, yet the sap reaches all parts of the plant and provides them nourishment.
Scientists unfold secret and project several theories in this regard. They describe many forces which are at work in this process. But no single theory is a complete explanationin itself.
In living things liquids and solutions pass through membranes and this process is called “Osmosis”. The osmotic pressure is one explanation. Depending upon the number of particles in a solution, the pressure is exerted against the membrane. This pressure and the ultimate seepage are directly proportional to the number of particles within the solution.
Roots are the carriers of minerals and water. The soil is richer in minerals than the plants and the osomotic pressure causes the rise of minerals from the soil into plants. The minerals solution remains in plant cells while the water evaporates from the soil below.
The evaporation of water from leaves is called “transpiration”. The cohesive attraction of water particles promotes rise of sap in plants to make up for th etranspiration lossese.
The upward pull caused by transpiration creates a vaccum down below. The plant cells draw more sap through the roots holding water particles due to cohesion.