In your own words what is photosynthesis and why do plants r

In your own words, what is photosynthesis and why do plants respire and photosynthesize at the same time.

Solution

Photosynthesis is the process by which plants and some other photosynthetic organisms utilize solar energy to produce carbohydrates from carbon dioxide and a reducing agent, water. In plants, solar energy is trapped to form ATP and NADPH in the light-dependent reaction, which is then used as an energy source to fuel the carbon assimilation reaction, which leads to production of carbohydrates and other organic compounds from CO₂ and H₂O. This conversion of energy is associated with the action of the green pigment chlorophyll.

Cellular respiration is the process by which complex mlecules like glucose are converted to CO₂ and H₂O. In ths process, ATP is generated. So, if you notice cellular respiration is the opposite of photosynthesis i.e. the products of one process are the reactants of the other. Photosynthesis generates glucose, which is broken down during cellular respiration to produce ATP, which used as a source of energy for the cell alongwith CO₂ which is again utilized during photosynthesis. Thus we can see that both the processes have to coexist. During the day the amount of photosynthesis exceeds that of cellular respiration, so glucose produced is higher during the day as compared to utilization (cellular respiration). But during night, since it is dark, photosynthesis cannot proceed and therefore the stored glucose is utilized. Thus, cellular respiration continues during the night providing the cell energy to carry out its functions. So, we can see that the products of one are being utilized as reactants in the other and this cycle continues.

This cycle of photosynthesis and cellular respiration maintains the balance of carbon dioxide and oxygen on earth. The life cycle of photosynthesis and cellular respiration thus sustains life on earth. Both are required to exist in symbiosis. Cellular respiration cannot occur without photosynthesis, and vice versa.