Question

multiple choice question

photosynthetic organisms use a sunlight-driven electron transport chain to generate atp via ______.

• substrate-level phosphorylation
• beta oxidation
• photophosphorylation
• oxidative phosphorylation

Explanation:

Identify the mechanism of ATP generation driven by sunlight

$$ \text{Sunlight} ightarrow \text{Electron Transport Chain (ETC)} ightarrow \text{Proton Motive Force} ightarrow \text{ATP Synthesis} $$

Evaluate the given options

• substrate-level phosphorylation: Direct transfer of a phosphate group from an organic substrate to ADP (occurs in glycolysis and Krebs cycle).
• beta oxidation: Metabolic process that breaks down fatty acids into acetyl-CoA.
• photophosphorylation: The synthesis of ATP using light energy delivered through a photosynthetic electron transport chain.
• oxidative phosphorylation: ATP synthesis driven by electron transfer from organic compounds to oxygen or other inorganic terminal electron acceptors in respiration.

Select the correct term

$$ \text{Sunlight-driven ATP synthesis} = \text{photophosphorylation} $$

Answer:

• substrate-level phosphorylation
• beta oxidation
• photophosphorylation (Correct answer)
• oxidative phosphorylation