What is common between NAD and FAD ?

Options

A. Both are coenzymes.
B. Both are derived from proteins
C. Both act as oxygen carriers
D. All of the above

Answer

To answer the question "What is common between NAD and FAD?", we can break down the solution into the following steps:

### Step 1: Define NAD and FAD
- **NAD** stands for Nicotinamide adenine dinucleotide.
- **FAD** stands for Flavin adenine dinucleotide.

### Step 2: Identify their roles
- Both NAD and FAD function as **coenzymes**. Coenzymes are organic molecules that assist enzymes in catalyzing reactions.

### Step 3: Describe their function in cellular respiration
- Both NAD and FAD play a crucial role in **accepting high-energy electrons** during metabolic processes, particularly in cellular respiration.
- After accepting these electrons, they transport them to the **electron transport chain**.

### Step 4: Explain the outcome of their function
- In the electron transport chain, the electrons are ultimately transferred to the final electron acceptor, which is **oxygen**. This process leads to the production of **ATP** (adenosine triphosphate) and **water**.

### Conclusion
- The commonality between NAD and FAD is that they are both coenzymes that accept high-energy electrons and transport them to the electron transport chain, facilitating ATP production.

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