Exnzyme concerned with the transfer of electrons is

Options

A. oxidoreductases
B. cytochrome oxidase
C. dehydrogenase
D. all of these

Answer

To solve the question regarding the enzyme concerned with the transfer of electrons, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the type of enzyme that is involved in the transfer of electrons.

2. **Know the Types of Enzymes**: Enzymes are classified into six main categories based on the type of reaction they catalyze:
- Oxidoreductases
- Transferases
- Hydrolases
- Lyases
- Isomerases
- Ligases

3. **Identify the Relevant Class**: Among these categories, oxidoreductases are the enzymes that specifically catalyze the transfer of electrons. This includes reactions where oxidation and reduction occur.

4. **Examples of Oxidoreductases**: Some common examples of oxidoreductases include:
- Dehydrogenases: These enzymes facilitate the removal of hydrogen (and thus electrons) from substrates.
- Cytochrome oxidase: This enzyme plays a crucial role in the electron transport chain and is involved in the transfer of electrons.

5. **Select the Correct Answer**: The question provides options: oxidoreductase, cytochrome oxidase, dehydrogenase, and all of these. Since both dehydrogenases and cytochrome oxidase fall under the category of oxidoreductases, the correct answer is "all of these."

### Final Answer:
The enzyme concerned with the transfer of electrons is **all of these** (oxidoreductase, cytochrome oxidase, and dehydrogenase).

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