photorespiration

American  

[foh-toh-res-puh-rey-shuhn] / ˌfoʊ toʊˌrɛs pəˈreɪ ʃən /

noun

1. the oxidation of carbohydrates in many higher plants in which they get oxygen from light and then release carbon dioxide, somewhat different from photosynthesis.

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photorespiration British  

/ ˌfəʊtəʊˌrɛspəˈreɪʃən /

noun

1. (in plants) a reaction that occurs during photosynthesis in which oxygen is assimilated and used to oxidize carbohydrates, with the release of carbon dioxide: differs from normal respiration in that there is no production of energy in the form of ATP

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photorespiration Scientific  

/ fō′tō-rĕs′pə-rā′shən /

1. The chemical combination of carbohydrates with oxygen in plants with the release of carbon dioxide. Photorespiration requires the presence of light, is catalyzed in the chloroplasts by the same enzymes that catalyze the combination of carbohydrates with carbon dioxide during photosynthesis, and occurs when oxygen concentrations in the cell are high. Photorespiration typically takes place during conditions of high light intensity, dryness, and heat (often resulting in the closure of stomata), when the amount of carbon dioxide entering the plant is reduced, and the amount of oxygen produced by photosynthesis accumulates. Photorespiration thus acts to produce carbon dioxide when it is unavailable and acts as a check on photosynthesis and on the productivity of the plant. Unlike cellular respiration, photorespiration does not produce any ATP or NADH, and so consumes chemical energy rather than produces it. Many angiosperms have a supplemental method of carbon-dioxide uptake that minimizes losses from photorespiration.

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Compare meaning

How does photorespiration compare to similar and commonly confused words? Explore the most common comparisons:

• photorespiration vs. photosynthesis

Example Sentences

See Examples For:

photorespiration

With an analysis of a global dataset of tree tissue, the research team demonstrated that the rate of photorespiration is up to two times higher in warmer climates, especially when water is limited.

From Science Daily ● Jan. 31, 2024

The methods will allow researchers to explicitly test existing hypotheses regarding the changing influence of plant photorespiration on climate over geologic time.

From Science Daily ● Jan. 31, 2024

The foreign genes enabled the trees to have lower photorespiration rates and to recycle carbon from phosphoglycolate into sugars essential to growth.

From Science Magazine ● Feb. 23, 2022

This chemical error, known as photorespiration, generates a toxic compound called glycolate that plants must break down.

From Nature ● Apr. 25, 2017

The C4 and CAM pathways are two adaptations—beneficial features arising by natural selection—that allow certain species to minimize photorespiration.

From Textbooks ● Jan. 1, 2015