Question

how does chemical combination take place in plants

Answer 1

Since plants require nutrients in the form of elements such as carbon and potassium, it is important to understand the chemical composition of plants. The majority of volume in a plant cell is water; it typically comprises 80 to 90 percent of the plant's total weight. Soil is the water source for land plants. It can be an abundant source of water even if it appears dry. Plant roots absorb water from the soil through root hairs and transport it up to the leaves through the xylem. As water vapor is lost from the leaves, the process of transpiration and the polarity of water molecules (which enables them to form hydrogen bonds) draws more water from the roots up through the plant to the leaves . Plants need water to support cell structure, for metabolic functions, to carry nutrients, and for photosynthesis.

Answer 2

in plants chemical combination occurs 
Ex:photosynthesis
photosynthesis is the process of converting light energy to chemical energy and storing in the form of sugar.this process takes place in chloroplasts with the help of chlorophyll.
reaction:
6CO2 + 6H2O + (light energy) -------> C6H12O6 + 6O2

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