When the electrons pass from one carrier to another via complex-I to IV in the electron transport chain, they are coupled to ATP synthase (complex-V) for the production of ATP from ADP and inorganic phosphate , is called

Answer

**Step-by-Step Solution:**

1. **Understanding the Electron Transport Chain (ETC)**: The electron transport chain is a series of protein complexes located in the inner mitochondrial membrane. It consists of four main complexes (Complex I to Complex IV) that facilitate the transfer of electrons derived from NADH and FADH2.

2. **Identifying the Complexes**:
- **Complex I**: NADH dehydrogenase
- **Complex II**: Succinate dehydrogenase
- **Complex III**: Cytochrome b-c1 complex
- **Complex IV**: Cytochrome c oxidase

3. **Electron Transfer Process**: As electrons move through these complexes, they are transferred from one carrier to another. This movement is coupled with the pumping of protons (H⁺ ions) across the inner mitochondrial membrane, creating a proton gradient.

4. **Coupling with ATP Synthase**: The proton gradient generated by the electron transport chain is utilized by ATP synthase (Complex V). As protons flow back into the mitochondrial matrix through ATP synthase, the enzyme catalyzes the conversion of ADP and inorganic phosphate (Pi) into ATP.

5. **Defining the Process**: The entire process, where the transfer of electrons is coupled with ATP production, is known as **oxidative phosphorylation**. This term specifically refers to the synthesis of ATP that is linked to the oxidation of electron carriers and the phosphorylation of ADP.

6. **Conclusion**: Therefore, the answer to the question is that the process when electrons pass from one carrier to another via Complex I to IV and are coupled to ATP synthase for ATP production is called **oxidative phosphorylation**.

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