Photosynthesis overall equation

ATP synthesis is not the only energy-conserving reaction of photosynthesis in plants the NADPH formed in the final electron transfer is (like its close analog NADH) also energetically rich. The overall equation for noncyclic photophosphorylation (a term explained below) is... 

For the chemically minded, the overall equation for photosynthesis can be given as COz + H20 —> CH20 (organic carbon in the form of carbohydrate) + 02 respiration can be given as the reverse reaction. This means that for every molecule of CHzO (or its equivalent in other organic matter) that is buried and not burned up by respiration, one molecule of 02 is left in the air. 

In 1862-64, Julius von Sachs could finally prove that chlorophyll is involved in photosynthesis. He worked out the overall equation of photosynthesis ... 

Therefore the original data and the review of the information available show that the overall equation of photosynthesis should contain both the light energy and the thermal one / 10,11 /. 

Carbohydrates are synthesized in green plants by photosynthesis—a process that uses solar energy to reduce, or fix, carbon dioxide. Photosynthesis in algae and higher plants occurs in cell organelles called chloroplasts. The overall equation for photosynthesis can be written as follows ... 

Photosynthesis in plants can be represented by the following overall equation ... 

The basic reactions of photosynthesis and respiration involve in fact a series of uphill and downhill hydrogen transfers via sophisticated electron transport chains eventually resulting in the splitting of water into hydrogen and oxygen or in its synthesis from them. For our purpose, however, these reactions can be summarized in a simplihed manner in accord with the two overall equations ... 

We must also take into account the fact that photosynthesis leads eventually to important products, the hexoses, that is carbohydrates containing six carbon atoms. This leads to a further revision of our overall equation ... 

Oxygen is generated naturally in photosynthesis, whereby plants synthesize carbohydrates, etc. from water and carbon dioxide in the atmosphere, using sunlight as the source of energy. The overall equation for the reaction is ... 

All the O atoms evolved as Og come from water none comes from carbon dioxide. But 12 O atoms are evolved as 6 Og, and only 6 O atoms appear as 6 HgO in the equation. Also, 6 COg have 12 O atoms, yet there are only 6 O atoms in CgHigOg. How can yon account for these discrepancies Hint Consider the partial reactions of photosynthesis ATP synthesis, NADP reduction, photolysis of water, and the overall reaction for hexose synthesis in the Calvin-Benson cycle.)... 

Equation 8.28 summarizes the overall steady-state balance of CO2 fluxes for leaves. These fluxes depend on temperature in different ways (Fig. 8-16). Net photosynthesis and respiration plus photorespiration can occur at leaf temperatures slightly below 0°C. Inhibition of gross photosynthesis can occur at temperatures above 35 to 40°C for many C3 species, often primarily reflecting damage to Photosystem II (e.g., Chapter 5, Section 5.5A). In such cases, net CO2 uptake (Eq. 8.28) can be optimal near 30°C (Fig. 8-16). 

Using Equation 8.30, we can relate the apparent or net rate of photosynthesis, /coz to the various resistances, the rate of respiration plus photorespiration, and the overall drop in CO2 concentration (Ac = Cq — c ). Let us rearrange Equation 8.30 into the following form ... 

The overall chemistry of photosynthesis, which takes place in green plants and many other living things, such as the algae in Figure 17, is described by the following endothermic equation. 

Chemical respiration, or cellular respiration, takes place in the cells of a plant or animal and is fueled by glucose and oxygen. The overall process is the opposite of the photosynthesis reaction, as shown in the following equation. 

Write the balanced chemical equation that describes the overall process in photosynthesis. 

Skill 22.2 Identifying the overall chemical equations for the metabolic reactions of photosynthesis and respiration. 

Respiration is a process that is, in many ways, a reversal of photosynthesis. Photosynthesis collects energy in the form of light to synthesize food in the form of glucose respiration involves the decomposition of glucose to acquire the necessary energy for life processes. Respiration may take place either aerobically (in the presence of oxygen) or anaerobically (in the absence of oxygen). The overall balanced chemical equation for aerobic respiration is written below. 

Stage 4 Carbon Fixation The ATP and NADPH generated by the second and third stages of photosynthesis provide the energy and the electrons to drive the synthesis of polymers of six-carbon sugars from CO2 and H2O. The overall balanced chemical equation is written as... 

In oxygenic photosynthesis, the hydrogen can only come from water, but the source of the oxygen is ambiguous. If we look at the overall chemical equation for photosynthesis, we see that it could come from either carbon dioxide or water ... 

In these reactions O2- is the electron donor, and C4 is the electron acceptor. Equations 4.1 and 4.2 are called half-reactions because they describe only half of the reaction. Although half-reactions appear to imply that free electrons exist, half-reactions imply only that the other half of the reaction is unspecified. The overall reaction of photosynthesis is the sum of the half-reactions ... 

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