Electron transport chain (ETC) is a set of______electroncarries present in a specific sequence along_______mitochondrial membrane.

Options

A. seven, inner
B. six,inner
C. seven,outer
D. six,outer

Explanation

**Step-by-Step Solution:**

1. **Identify the Components of the Electron Transport Chain (ETC):**
The electron transport chain consists of a series of electron carriers. In this case, we need to determine how many electron carriers are present in the ETC.

2. **List the Electron Carriers:**
The main electron carriers in the ETC include:
- Plastoquinone
- Cytochrome b
- Cytochrome c
- Cytochrome c1
- Cytochrome a1
- Cytochrome a3
- Oxygen (O2) as the final electron acceptor

Thus, there are **seven electron carriers** in total.

3. **Determine the Location of the ETC:**
The electron transport chain occurs in the mitochondrial membrane. It is essential to identify whether it takes place in the inner or outer mitochondrial membrane.

4. **Identify the Correct Membrane:**
The electron transport chain is located in the **inner mitochondrial membrane**. This is where the electron carriers are embedded and where the process of oxidative phosphorylation occurs.

5. **Formulate the Complete Answer:**
Therefore, the electron transport chain (ETC) is a set of **seven electron carriers** present in a specific sequence along the **inner mitochondrial membrane**.

**Final Answer:**
Electron transport chain (ETC) is a set of **seven electron carriers** present in a specific sequence along the **inner mitochondrial membrane**.

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