Glycolate generated during photorespiration crosses into microbodies known as____________?
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Answer: B. Peroxisomes
Explanation
During photorespiration, glycolate produced in chloroplasts is transferred to peroxisomes for further metabolic processing. Inside peroxisomes, glycolate is oxidized to glyoxylate with the concurrent production of hydrogen peroxide. This pathway involves coordinated cooperation between chloroplasts, peroxisomes, and mitochondria. Photorespiration occurs when Rubisco fixes oxygen instead of carbon dioxide under high light and heat. Peroxisomes contain catalase enzymes to safely break down toxic hydrogen peroxide generated during this process. The pathway is energetically costly for plants but serves to salvage carbon units from glycolate.
Plant physiology research aims to engineer crop plants with reduced photorespiration to improve agricultural yields. Understanding microbody functions reveals how plant cells compartmentalize toxic metabolic intermediates. C4 and CAM plants have evolved mechanisms to concentrate carbon dioxide and minimize photorespiratory losses. Glyoxisomes are specialized plant peroxisomes involved in converting stored lipids into sugars during germination. Lysosomes are animal cell organelles containing digestive enzymes for breaking down cellular waste. Mitochondria participate later in the photorespiratory cycle to release carbon dioxide and recover ammonia.
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