Question

Why is photosynthesis considered an endothermic reaction?

Answer 1

Photosynthesis is a physicochemical process by which photosynthetic organisms drive the synthesis of organic compounds by using light energy. In the process of photosynthesis, photosynthetic organisms first convert light energy into chemical energy in the form of NADPH and ATP and later use these chemicals to reduce $C{O_2}$ into organic compounds (termed carbon dioxide fixation).

Complete answer:
Most of the important series of endothermic reactions on Earth is photosynthesis. The steps occur in the process. But, the overall chemical reaction is as follows:
$6C{O_2}{\text{ }} + {\text{ }}6{H_2}O{\text{ }} \to {C_6}{H_{12}}{O_6}{\text{ }} + {\text{ }}6{O_2}$
Disparate, many other endothermic reactions, photosynthesis does not absorb energy as heat.
Rather, plants absorb energy from sunlight and turn that into carbon dioxide and water into oxygen and glucose, which is a type of sugar molecule.
Glucose molecules stored energy, ready to be used when needed. But, when you think about exothermic and endothermic reactions, consider energy to be part of the reaction.
An exothermic reaction releases energy so that the energy is on the product side of the chemical equation and an endothermic reaction absorbs energy so that the energy is on the reactant side of the chemical equation.
Photosynthesis requires several different chemical reactions, but these can be summarised in two main stages.
Let me explain to you about reactions, in the first reaction, energy is used to split water molecules into hydrogen and oxygen and the hydrogen is needed for the second stage of reactions.
The oxygen is released by the plant as a waste product (but useful to human beings). And in the reactions of the second stage, the hydrogen is combined with carbon dioxide to make glucose, which gives energy.

Note:
The glucose produced by photosynthesis is used for respiration by human beings. Glucose is the starting point of the biosynthesis of the materials that plants need to live. The association between photosynthesis and cellular respiration is such that the products of one system are the reactants of the other. Photosynthesis involves the use of energy from sunlight (vitamin D), water, and carbon dioxide to produce glucose and oxygen. Cellular respiration produces carbon dioxide and water by using glucose and oxygen.