What happens in the Electron transport chain?

Explanation

### Step-by-Step Solution:

1. **Location of the Electron Transport Chain (ETC)**:
- The Electron Transport Chain occurs in the mitochondria, specifically across the inner mitochondrial membrane.

2. **Structure of Mitochondria**:
- The mitochondria consist of two membranes: an outer mitochondrial membrane and an inner mitochondrial membrane. The space between these membranes is known as the intermembrane space, while the area enclosed by the inner membrane is called the mitochondrial matrix.

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