AP BIOLOGY

Detailed explanation-1: -Phosphoglycolate formed by oxygen fixation is recycled to the Calvin cycle intermediate phosphoglycerate in the photorespiratory pathway. This reaction cascade consumes energy and reducing equivalents and part of the afore fixed carbon is again released as CO2.

Detailed explanation-2: -In the photorespiration pathway, RuBP binds to O2 to create one molecule of PGA (3C chemical) and phosphoglycolate (2C compound). There is no sugar synthesis or ATP synthesis. Rather, it results in the emission of CO2 as a result of the use of ATP. It results in a 25% reduction in stationary CO2 emissions.

Detailed explanation-3: -Photorespiration wastes energy and steals carbon Two molecules are produced: a three-carbon compound, 3-PGA, and a two-carbon compound, phosphoglycolate.

Detailed explanation-4: -The photosynthetic carboxylation reaction yields two molecules of 3-phosphoglycerate (3PGA), which enter the C3 carbon reduction or Calvin cycle, whereas oxygenation, which competitively inhibits carboxylation, produces one molecule of 3PGA and one molecule of the 2-carbon compound phosphoglycolate.