When adenine is attached to ribose sugar, it is called adenosine . To make a nucleotide from it, would require

Options

A. oxygenation
B. addition of a base
C. addition of phosphate
D. hydrogenation

Answer

To convert adenosine into a nucleotide, we need to follow these steps:

### Step-by-Step Solution:

1. **Understanding Adenosine**:
- Adenosine is formed by the combination of adenine (a nitrogenous base) and ribose sugar.
- The structure of adenosine consists of the ribose sugar with the adenine base attached to it.

2. **Identifying the Components of a Nucleotide**:
- A nucleotide is made up of three components: a nitrogenous base, a sugar (ribose in this case), and a phosphate group.
- Therefore, to convert adenosine into a nucleotide, we need to add a phosphate group to the existing structure of adenosine.

3. **Adding the Phosphate Group**:
- The phosphate group (PO4^3-) can be added to the 5' carbon of the ribose sugar in the adenosine structure.
- This results in the formation of adenosine triphosphate (ATP) if three phosphate groups are added, or adenosine monophosphate (AMP) if only one phosphate group is added.

4. **Final Structure**:
- The final structure of the nucleotide (AMP or ATP) will include the ribose sugar, the adenine base, and the phosphate group(s) attached to the ribose sugar.

5. **Conclusion**:
- To summarize, to make a nucleotide from adenosine, the required step is the addition of a phosphate group.

### Answer:
To make a nucleotide from adenosine, it would require the addition of a phosphate group.

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