Which of the following diagram represents of ATP synthesis in mitochondria through chemiosmosis -
I.M = Inner membrane
M = Matrix
O.C = Outer Chamber

Options

A.
B.
C.
D.

Answer

To determine which diagram represents ATP synthesis in mitochondria through chemiosmosis, we need to understand the process of ATP synthesis and the role of the mitochondrial structures involved.

### Step-by-Step Solution:

1. **Identify the Components**:
- The inner membrane (I.M) of the mitochondria is where ATP synthesis occurs.
- The mitochondrial matrix (M) is the space inside the inner membrane.
- The outer chamber (O.C) is the space between the inner and outer membranes.

2. **Understand the Process of Chemiosmosis**:
- During cellular respiration, electrons are transferred through the electron transport chain located in the inner membrane.
- This electron flow causes protons (H+) to be pumped from the mitochondrial matrix into the outer chamber, creating a proton gradient.

3. **Proton Motive Force**:
- The accumulation of protons in the outer chamber generates a proton motive force (PMF).
- Protons flow back into the matrix through ATP synthase (the complex responsible for ATP synthesis), which is also located in the inner membrane.

4. **ATP Synthesis**:
- As protons flow through ATP synthase, the energy from this movement is used to convert ADP and inorganic phosphate into ATP.

5. **Analyze the Diagrams**:
- Look for a diagram that shows:
- Protons being pumped from the matrix to the outer chamber.
- Protons flowing back into the matrix through ATP synthase.
- The formation of ATP from ADP and inorganic phosphate.

6. **Select the Correct Diagram**:
- Based on the description, the diagram that shows protons moving from the outer chamber back into the matrix through ATP synthase and depicts the synthesis of ATP is the correct representation of chemiosmosis in mitochondria.

### Conclusion:
The correct diagram that represents ATP synthesis in mitochondria through chemiosmosis is **Option 3**, as it accurately depicts the flow of protons and the generation of ATP.

---