Simple Essay: NONCYCLIC pathway of photosynthesis …

In this cycle the end products of the light-dependent reaction are used.

Cyclic & Noncyclic Electron Flow - YouTube

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.

II. Non-Cyclic Electron Pathway - Bio12U - Google Sites

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.

C4 pathway
C4 cycle is the pathway adopted by C4 plants to conserve the carbon dioxide released via photorespiration. It adopts a new enzyme (PEPC, Phosphoenol pyruvate carboxylase) which does not react with oxygen; it also adopted a separated compartment for CO2 up taking and fixation.


Cyclic and Noncyclic Photophosphorylation

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.

What is non-cyclic photosynthesis and how is it ..

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.

Section summary, The cyclic pathway of photosynthesis…

Light reaction and photophosphorylation
Pigments embedded on thylakoid membranes form photosystems. There are of two types: PS I P700, PS II P680. Components of photosystem I and II transfer the electrons from water to NADP via cyclic electron transfer or non-cyclic electron transfer. During electron transfer, the light energy captured by the photosynthetic organisms is transformed into the phosphate bond energy of ATP. This is called photophosphorylation. NADPH is generated during non-cyclic electron transfer.

What is non-cyclic photosynthesis and how is ..

The regeneration of RuBP is essential for carbon fixation to continue. Five triose phosphate molecules will undergo a series of reactions requiring energy from ATP, to form three molecules of RuBP. RuBP is therefore consumed and produced during the light-independent reactions and therefore these reactions form a cycle which is named the Calvin cycle.