Differences between light reaction and dark reaction ?

Question

Answer

Light reaction is the stage of photosynthesis which occurs only in the presence of sunlight and it is depend on the light to perform it's work......It takes place in the grana thylakoid membrane of the chloroplast.....The grana grana thylakoid is responsible for trapping the solar energy for photosynthesis.....Dark reaction is the stage of photosynthesis which occurs in presence or absence of light.....It is not dependent on light to perform it's reaction.....It takes place in the stroma of the chloroplast.....The stroma is responsible for enzymatic reaction to synthesise of glucose to form starch.....

Answer

Light reaction: The light reaction of photosynthesis occur in grana of chloroplast. They involves photophosphorylation and photolysis of water leading to formation of NADPH2.          Dark reaction: The dark reaction occur in photosynthesis in stroma of chloroplast.

Answer

Differences Between Light Reaction and Dark Reaction

Light Reaction

Occurs in the thylakoid membrane of the chloroplasts in the presence of light.

It is the first step of photosynthesis.

It converts light energy into chemical energy in the form of ATP and NADPH.

It involves the splitting of water molecules to produce oxygen gas and hydrogen ions which are used to produce ATP and NADPH.

The reaction occurs in the presence of pigments such as chlorophyll, carotenoids, and phycobilins.

It is also called the light-dependent reaction or the photochemical reaction.

The reaction is temperature-sensitive and is optimal at temperatures between 0°C and 35°C.

It requires light, water, and chlorophyll.

Dark Reaction

Occurs in the stroma of the chloroplasts in the absence of light.

It is the second step of photosynthesis.

It uses the chemical energy produced during the light reaction to convert carbon dioxide into glucose.

It is also called the light-independent reaction or the Calvin cycle.

The reaction occurs at a constant rate and is not temperature-sensitive.

It does not require light but requires ATP and NADPH produced during the light reaction.

The reaction involves the fixation of carbon dioxide into a stable organic compound, which is then used to synthesize glucose and other carbohydrates.

It is an enzyme-mediated process and involves several enzymes such as Rubisco, which is responsible for the fixation of carbon dioxide.

Conclusion

In conclusion, the light reaction and dark reaction are two important steps in the process of photosynthesis. The light reaction occurs in the presence of light and converts light energy into chemical energy in the form of ATP and NADPH. The dark reaction, on the other hand, occurs in the absence of light and uses the chemical energy produced during the light reaction to convert carbon dioxide into glucose. Understanding the differences between these two reactions is important in understanding the overall process of photosynthesis.

Answer

Light reactions are required to produce ATP and NADPH by using light and dark reactions use them to synthesis the food that is carbohydrates or glucose.but the main difference is light reactions occur only in the presence of sunlight and dark occur in both light as well as dark.

Answer

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