[Campbell Biology P.171] If a plant cell is deprived of light, which specific enzyme's funct... | Practice Question

If a plant cell is deprived of light, which specific enzyme's function within the chloroplast, as detailed in Figure 6.32 c , would be most directly impacted, leading to a halt in sugar production?

  • A: ATP synthase
  • B: Rubisco
  • C: Photosystem I
  • D: Hexokinase

Explanation

Figure 6.32 c explains that photosynthesis 'produces sugars that provide food for all life on the planet' and 'rubisco and other proteins in the stroma to make sugars.' Rubisco is the enzyme directly responsible for fixing carbon dioxide into organic molecules, which leads to sugar production. This process requires ATP and NADPH generated by the light-dependent reactions which involve Photosystem I, etc. . Without light, ATP and NADPH cannot be produced, and thus Rubisco's function, essential for sugar synthesis, would cease.