Energy V - Photosynthesis (Calvin Cycle) - …
The energy from ATP and the reducing power of NADPH (both produced during the light-dependent reactions) is now used to convert the molecules of PGA to glyceraldehyde-3-phosphate (G3P), another three-carbon compound (see Fig. 1). For every six molecules of CO2 that enter the Calvin cycle, two molecules of G3P are produced. Most of the G3P produced during the Calvin cycle - 10 of every 12 G3P produced - are used to regenerate the RuBP in order for the cycle to continue (see Fig. 1). Some of the molecules of G3P, however, are used to synthesize glucose and other organic molecules. As can be seen in Fig. 1, two molecules of the three-carbon G3P can be used to synthesize one molecule of the six-carbon sugar glucose. The G3P is also used to synthesize the other organic molecules required by photoautotrophs (see Fig. 2).
SAPLING CH 5 HW Flashcards | Quizlet
The Calvin cycle assembles sugar mlecules from CO2 using the energy-carrying products of the light reactions.
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The Light Reactions: Converting Solar Energy to Chemical Energy. () Certain wavelengths of visible light drive the light reactions of photosynthesis.
3. As mentioned in the previous step, most of the G3P produced during the Calvin cycle - 10 of every 12 G3P produced - are used to regenerate the RuBP so that the cycle may continue. Ten molecules of the three-carbon compound G3P eventually eventually form six molecules of the four-carbon compound ribulose phosphate (RP). Each molecule of RP then becomes phosphorylated by the hydrolysis of ATP to produce ribulose bisphosphate (RuBP), the starting compound for the Calvin cycle.
Fructose-bisphosphate aldolase - Wikipedia
: ATP is used to reconstitute RuBP from G3P
Where's the Sugar?
In order to get 1 G3P as a product of the Calvin Cycle, 3 molecules of carbon dioxide have to be joined to three molecules of RuBP.
Cellular Respiration Flashcards | Quizlet
Photosynthesis is a process where by energy from light is harvested and used to drive synthesis of organic carbohydrates from carbon dioxide and water. Photosynthesis takes place in chloroplasts and can be divided into two steps: light reactions which require light and dark reactions which do not require light. During light reaction, light energy is captured by photosystems and electrons are transferred among the electron receptors. ATP and NADPH are generated. During dark reactions, CO2 is fixed using ATP and NADPH generated by the light reactions and organic carbohydrates are synthesized via the Calvin Cycle. When the CO2 is first fixed into a 3 carbon compound 3PGA, it is called C3 pathways and these plants are called C3 plants. The disadvantage of C3 plants is that they undergo photorespiration and thus waste some energy gained in light reactions. C4 cycle is the pathway adopted by C4 plants to bypass photorespiration.
Part of our Photosynthesis Learning Guide
Dark reaction – Calvin cycle
Second step of photosynthesis is called Calvin’s cycle. Because it does not require light, so it is called dark reaction. During dark reaction, the ATP and NADPH generated by light reaction are consumed to fix carbon dioxide into organic carbohydrates. The first fixed carbohydrate is a three carbon compound 3-phosphoglycerate (3PGA). The final product is a high-energy 3 carbon compound glyceraldehyde-3-phosphate (G3P) which can be used to synthesize a broad range of organic molecules. An important intermediate molecule for carbon dioxide fixation is ribulose bisphosphate (RuBP), and the enzyme catalyzing the CO2 fixation is Rubisco.
Chemistry for Biologists: Photosynthesis
The thykaloid membranes contain chlorophyll, the green pigment that captures light for photosysthesis.
The complete process of photosynthesis consists of two linked sets of reactions: the light reactions and the Calvin cycle.