Transfer of light energy by intermediate energy carriers 3.
There is also light-independent photosynthesis, which USES ATP and creates glucose from carbon dioxide and water, producing oxygen as a waste product. This is really an energy storage mechanism, so that the organism doing it can later burn the glucose through glycolysis and respiration. This also happens in chloroplasts, so plants can, and animals can't.
Light energy is converted to what kind of energy in photosynthesis
The light-dependent reactions
produce oxygen gas
and convert ADP and NADP+ into the energy carriers
ATP and NADPH.
move through the electron transport chain from photosystem II to photosystem I.
As electrons are passed from
to NADP+, more H+ ions are pumped across the membrane.
Because of this system, light-dependent electron transport produces not only high-energy electrons but
What is the Calvin cycle's function?
The Calvin Cycle
The Calvin cycle uses
from the light-dependent reactions to fix CO producing high-energy
The Calvin Cycle
The energy for this conversion comes from
and high-energy electrons from
The Calvin Cycle
The cycle continues with more input of energy from
Figure 6: Photosynthesis takes place in two stages: light dependent reactions and the Calvin cycle. Light-dependent reactions, which take place in the thylakoid membrane, use light energy to make ATP and NADPH. The Calvin cycle, which takes place in the stroma, uses energy derived from these compounds to make GA3P from CO2.
They explain the role of intermediate energy carriers to ..
-light-dependent photosynthesis, in which electrons are cycled around photosynthetic pigments after being jostled around by mid-high-energy photons (light particles), which filter through an electron pump that makes ATP. This happens in chloroplasts, and as such only occurs in plants.
Transfer of light energy by intermediate energy carriers 3
The light energy is converted to chemical energy, in the form of ATP and NADPH, using the light-dependent reactions and is then available for carbon fixation.
as its primary energy source in photosynthesis.
Although there is a large variety, each item links back to photosynthesis. Meats and dairy link, because the animals were fed plant-based foods. The breads, cereals, and pastas come largely from starchy grains, which are the seeds of photosynthesis-dependent plants. What about desserts and drinks? All of these products contain sugar—sucrose is a plant product, a disaccharide, a carbohydrate molecule, which is built directly from photosynthesis. Moreover, many items are less obviously derived from plants: For instance, paper goods are generally plant products, and many plastics (abundant as products and packaging) are derived from algae. Virtually every spice and flavoring in the spice aisle was produced by a plant as a leaf, root, bark, flower, fruit, or stem. Ultimately, photosynthesis connects to every meal and every food a person consumes.
Excitation energy transfer in photosynthesis - …
Initially, pyruvate is oxidized and decarboxylated in a complexreactioninvolving NAD, Coenzyme A, and pyruvate dehydrogenase (pyruvatedecarboxylase),forming the most central molecule in metabolism, Acetyl CoA. (SeeFigure4). Acetyl CoA condenses with the 4C-compound, oxalacetic acid, to formthe first stable intermediate of the TCA cycle, 6C-citric acid(citrate),a tricarboxylic acid. Citrate is isomerized to isocitrate, which isoxidizedand decarboxylated forming alpha-ketoglutarate (akg). Alphaketoglutaratedehydrogenase uses CoA and NAD to oxidize akg to succinyl CoA in areactionanalogous to the pyruvate dehydrogenase reaction above. Succinyl CoA isconverted to succinate during a substrate level phosphorylationyieldinghigh energy GTP (equivalent to ATP). This completes the decarboxylationof pyruvate forming 3 CO2. The remaining three steps in thecycle complete the oxidation of succinate and regenerate theoxalacetatenecessary to drive the cycle. During the oxidation of pyruvic acid to 3CO2 by one turn of the TCA cycle, 4 NADH2, 1 FADH2 and oneATP(actually GTP) are produced. Since the TCA cycle is an importantamphibolicpathway, several intermediates of the cycle may be withdrawn foranabolic(biosynthetic) pathways (See Figure 25).
In photosynthesis of types A and B, light energy is ..
Energy to make ATP in the chloroplast comes most directly from
hydrogen ions flowing through an enzyme in the thylakoid membrane.