According to chemiosmotic of P. Mitchell (1978), ATPs are synthesised on membranes due to the

Options

A. Proton gradient
B. Electron gradient
C. Osmosis
D. From `H_(2)SO_(4)`

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Chemiosmotic Theory**: The chemiosmotic theory proposed by Peter Mitchell in 1978 explains how ATP is synthesized in cells, particularly during cellular respiration.

2. **Location of ATP Synthesis**: ATP synthesis occurs in the inner mitochondrial membrane, where the electron transport chain (ETC) is located.

3. **Role of the Electron Transport Chain (ETC)**: The ETC consists of a series of protein complexes that transfer electrons. As electrons move through these complexes, they release energy.

4. **Formation of Proton Gradient**: The energy released during electron transfer is used to pump protons (H⁺ ions) from the mitochondrial matrix into the intermembrane space, creating a proton gradient (higher concentration of protons outside the matrix compared to inside).

5. **ATP Synthesis Mechanism**: The proton gradient generated creates a potential energy difference across the membrane. Protons flow back into the mitochondrial matrix through ATP synthase, a protein complex that synthesizes ATP from ADP and inorganic phosphate (Pi).

6. **Conclusion**: According to Mitchell's chemiosmotic theory, ATP is synthesized on membranes due to the proton gradient established by the electron transport chain.

**Final Answer**: ATPs are synthesized on membranes due to the proton gradient.

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