BIOL-2356EL Lecture Notes - Lecture 5: Rubisco, Stoma, Leaf
4 Mar 2020
School
Department
Course
Professor
Document Summary
Autotrophic organisms: use only inorganic resources i. e solar/ chemical energy (co2 h2o mineral nutrient ions). Absorb co2 into organic molecules and living tissue. Photoautotrophs: solar energy -convert co2 to organic molecules in photosynthesis. Chemoautotrophs: energy from oxidation of inorganic atoms (s, s 2- , fe 2+ ) -convert co2 into organic molecules in chemosynthesis. Photosynthesis is a crucial process of carbon cycling: Global total of c cycled by photosynthesis: ~200-250 gigatonnes carbon/ year. Majority of products of photosynthesis are used by autotrophic respiration and heterotrophic consumption. Energy fixed by photosynthesis can be liberated in respiration/decomposition or combustion. Net primary production (npp): photosynthesis minus autotrophic respiration. Net ecosystem production (nep): npp minus consumption by heterotrophs. Photosynthesis occurs in the chloroplasts of palisade parenchyma tissue of the mesophyll of plant leaves. Tropics contribute the most global net primary production (npp) Global npp is increasing due to warmer temperature and higher co2.
