Question

photosynthesis is a combination reaction while respiration is a decomposition reaction. Give reason

Answer 1

in photosynthesis the constituents particles co2 from air water from soil and light from sun combines and help in making of food so it is a catabolic process
in case of respiration the food we take is burned with the help of oxygen ( by breathe) and provide energy to the body and it is anabolic process
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Answer 2

Carbon dioxide is a waste product of respiration and is formed from carbon and oxygen which were originally part of the food molecules. Heat energy may be released from cells during respiration. ... Respiration is a combustion reaction. We cannot readily classify it as combination or thermal decomposition.
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