Lesson Worksheet: The Light-Dependent Reactions Biology

In this worksheet, we will practice describing the reactions that occur in the light-dependent stage of photosynthesis and recalling the products formed.


What is the primary role of the proton pumps in the thylakoid membrane?

  • ATo allow the diffusion of H⁺ ions from the thylakoid lumen into the stroma
  • BTo absorb wavelengths of light to provide the energy needed for the light-dependent reaction
  • CTo actively transport H ions from the stroma into the interior of the thylakoid (the lumen)
  • DTo transport electrons along the electron transport chain


Which of the following tables correctly summarizes what happens to substances involved in the light-dependent reactions?

  • A
    EffectSynthesized SynthesizedReduced
  • B
    EffectPhotolyzed SynthesizedOxidized
  • C
    EffectPhotolyzed SynthesizedReduced
  • D
    EffectOxidized SynthesizedOxidized


Which of the following are products of the light-dependent reactions in photosynthesis?

  • AATP and water
  • BNADH and FADH
  • CADP and NADP
  • DATP and NADPH


Where in the chloroplast do the light-dependent reactions take place?

  • AIn the inner membrane
  • BIn the stroma
  • CIn the cristae
  • DIn the thylakoid membrane


At the beginning of the light-dependent reactions, water is split using light energy in a reaction known as photolysis.

What is produced when water is split in photolysis?

  • AH+, oxygen, and electrons
  • BH(g)2 and O(g)2
  • CO, H2, and protons


A product of the light-dependent reactions is oxygen. What specific process produces oxygen?

  • AThe photolysis of water
  • BThe phosphorylation of ADP
  • CThe movement of electrons through the electron transport chain
  • DThe active transport of hydrogen ions


What happens to the coenzyme NADP+ in the light-dependent stage of photosynthesis?

  • AIt loses electrons and a phosphate ion to become NAD.
  • BIt gains an oxygen ion to become oxidized NADP (NADPO+)
  • CIt gains electrons and H+ ions to become reduced NADP (NADPH).
  • DIt loses electrons and a H+ ion to form NADP+.


What is the primary role of ATP synthase in the light-dependent reactions?

  • ATo actively transport H+ ions from the stroma and into the thylakoid lumen
  • BTo phosphorylate ADP to create ATP
  • CTo actively transport electrons along the electron transport chain
  • DTo absorb wavelengths of light to provide the energy needed for the light-dependent reactions


Which charged particle generates the energy required for the phosphorylation of ADP when it moves through ATP synthase?

  • AH+
  • Be
  • CP+
  • DO


The diagram provided shows a simple outline of the light-dependent reaction, with key reactants and products removed.

What reactant has been replaced with label 1?

  • AADP
  • CWater
  • DFAD

What product has been replaced with label 2?

  • AOxygen
  • CATP

Practice Means Progress

Boost your grades with free daily practice questions. Download Nagwa Practice today!

scan me!

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.