What is one of the consequences of photorespiration?

Photorespiration is a metabolic process that occurs in plants, particularly under conditions of high oxygen concentration and low carbon dioxide levels. One of the significant consequences of photorespiration is the wasting of ATP and NADPH. During this process, oxygen is mistakenly utilized instead of carbon dioxide by the enzyme RuBisCO in the Calvin cycle, which leads to the production of a two-carbon compound instead of the usual three-carbon compound (3-PGA). This inefficiency requires the plant to expend energy in the form of ATP and reducing power in the form of NADPH to convert the two-carbon compound back into a usable form, resulting in a net loss of energy and reducing the overall efficiency of photosynthesis.

In contrast, increased sugar production, enhanced light absorption, and improved water efficiency are not direct consequences of photorespiration. Instead, these aspects are generally associated with efficient photosynthetic processes rather than the side reactions caused by photorespiration, which are considered detrimental to plant productivity.