<u><em>-How does night or darkness affect the light-independent reaction?
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Light independent reactions require the energy gathered in the thylakoids. While the Calvin cycle doesn't directly need light, without energy input from the light-dependent reactions, it will run out of steam pretty quickly. Light independent reactions need more heat energy than nighttime temperatures often provide. Mitochondria produce sugars more effectively in the darkness than chloroplasts do. Light independent reactions require the energy gathered in the thylakoids.
<u><em>-What is the importance of the concentration differences of Hydrogen ions (H+) inside and outside the thylakoids? What would happen if it was equal and there was no concentration gradient?
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The accumulation of H+ allows synthesis of ATP molecules and NADPH needed to drive the synthesis of organic molecules in the plant cells. The intramembrane proteins work based on that concentration gradient. If the concentration is the same, the anabolic step of the photosynthesis doesn't take place.