Final answer:
Substrate-level phosphorylation is the type of phosphorylation that occurs at the level of a substrate without the involvement of the respiratory chain. An example is the conversion of phosphoenolpyruvate to pyruvate by pyruvate kinase, resulting in the formation of ATP from ADP.
Step-by-step explanation:
The synthesis of ATP and Pi, when coupled with an exergonic chemical reaction, is called substrate-level phosphorylation. This type of phosphorylation occurs at the level of a substrate without the involvement of the respiratory chain. An example of substrate-level phosphorylation is when phosphoenolpyruvate is converted to pyruvate by pyruvate kinase, and ATP is formed from ADP.