Summary
Rubisco binds oxygen instead of carbon dioxide, wasting energy and releasing CO2.
In depth
Rubisco's oxygenase activity makes phosphoglycolate, recovered through a costly pathway through peroxisomes and mitochondria, releasing CO2 and losing up to 25 percent of fixed carbon. It increases at high temperature.
It wastes energy but may protect against photodamage by consuming excess ATP and NADPH. Rates rise with temperature as rubisco's oxygenation increases relative to carboxylation and the solubility of CO2 falls.
Remember: it is not related to cellular respiration, despite the name.
Frequently asked questions
What is Photorespiration?
Rubisco binds oxygen instead of carbon dioxide, wasting energy and releasing CO2.
Which area of biology covers Photorespiration, and how advanced is it?
Photorespiration is one of the 56 topics in Plant Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Rubisco, C4 Photosynthesis, Calvin Cycle.
Can you give an example of Photorespiration?
C4 and CAM plants reduce it.
What should I learn before Photorespiration?
Work through the Beginner topics in Plant Biology first, such as Plant Kingdom, Photosynthesis, Chlorophyll, then return to Photorespiration. Advanced topics assume the Intermediate vocabulary.
What topics are related to Photorespiration?
The closest topics to Photorespiration are Rubisco, C4 Photosynthesis, Calvin Cycle, Photosynthesis Efficiency Engineering. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Photorespiration?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Photorespiration. To practise the whole of Plant Biology, use the Plant Biology quiz.
How is Photorespiration different from Rubisco?
Photorespiration: Rubisco binds oxygen instead of carbon dioxide, wasting energy and releasing CO2. Rubisco: The enzyme that fixes carbon dioxide in the Calvin cycle and is likely the most abundant protein on Earth. Read both side by side and note what each one explains.
How should I study Photorespiration step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Rubisco and explain the difference aloud. Finally, take the Plant Biology quiz and come back to this page for any question you miss.