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Unformatted text preview: C 4 pathway Some plants, notably grasses of tropical origin, have developed a means of subverting photorespiration by using a method called the Hatch-Slack or C 4 Pathway , named for its discoverers and its first product, oxaloacetic acid , a 4-carbon organic acid. A structural modification of the leaves accompanies the biochemical differences in this system: The leaf veins are surrounded by a cylinder of enlarged bundle sheath cells around which there usually is another layer of modified mesophyll cells. In cross-section view the two appear as rings of modified tissue, which gives the term Kranz anatomy (from the German word for wreath) to the leaf condition. The bundle sheath cells, in addition, contain functional chloroplasts unlike the sheath cells of C 3 plants. The first part of the C 4 pathway takes place in the mesophyll cells, the second partwhich is an ordinary...
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This note was uploaded on 11/14/2011 for the course BIO 1421 taught by Professor Farr during the Fall '08 term at Texas State.
- Fall '08