Number of multiprotein complexes in ETS in mitochondria is

Options

A. 2
B. 3
C. 4
D. 5

Answer

To determine the number of multiprotein complexes in the Electron Transport System (ETS) in mitochondria, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Electron Transport System (ETS)**: The ETS is a series of protein complexes located in the inner mitochondrial membrane that facilitate the transfer of electrons derived from NADH and FADH2 to oxygen, ultimately producing ATP.

2. **Identify the Multiprotein Complexes**: In the ETS, there are four main multiprotein complexes. These complexes are crucial for the electron transport process.

3. **List the Complexes**:
- **Complex I**: Known as NADH ubiquinone reductase.
- **Complex II**: Known as succinate ubiquinone reductase.
- **Complex III**: Known as ubiquinone-cytochrome c reductase.
- **Complex IV**: Known as cytochrome c oxidase.

4. **Count the Complexes**: From the list, we can see that there are a total of four distinct multiprotein complexes involved in the ETS.

5. **Select the Correct Option**: Given the options (2, 3, 4, and 5), the correct answer is 4.

### Final Answer:
The number of multiprotein complexes in the Electron Transport System in mitochondria is **4**.

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