BIOL 1020 Lecture Notes - Lecture 23: C4 Carbon Fixation, Vascular Bundle, Light-Independent Reactions

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1020
• Professor: Dilukshi Fernando

Document Summary

Lecture 23: summary of c4 plants, cam plants & cell. Alternative pathways of co2 fixation: when stomata closes to minimize water loss, co2 concentration decrease, o2 from light reaction starts accumulating, rubisco binds with o2 instead of co2, photorespiration takes place. The c4 pathway: fix carbon into a 4c compound, increase co2 concentration near rubisco by : a) carbon fixation occurs in mesophyll cells by pep carboxylase (has a higher affinity to. Co2) b) calvin cycle occurs in chloroplasts of bundle sheath cells (tightly packed sheaths around veins): e. g. in sugar cane, corn, grasses. Cam plants: co2 accumulation and fixation at night (when stomata are open, calvin cycle during the day (while stomata are closed to avoid excess water loss), e. g. cacti, pineapple. Cell signaling: epinephrine is also adrenaline, paracrine signaling: travel short distances and affect cells that are nearby, using fig 11. 6: a) reception occurs at plasma membrane and receptor changes shape.