Glucose is

Options

A. aldose hexose sugar
B. ketose hexose sugar
C. pyranose pentose sugar
D. furanose pentose sugar

Answer

To answer the question "Glucose is," we need to analyze the options provided and the characteristics of glucose.

### Step-by-Step Solution:

1. **Identify the Chemical Formula**:
- Glucose has the molecular formula C6H12O6. This indicates it contains 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms.

2. **Determine the Type of Sugar**:
- Glucose is classified as a carbohydrate. Carbohydrates are categorized based on the number of carbon atoms they contain. Since glucose has 6 carbon atoms, it falls under the category of hexose sugars.

3. **Identify the Functional Group**:
- The structure of glucose contains an aldehyde group (-CHO) at the first carbon atom. This is a key feature that classifies glucose as an aldose sugar.

4. **Conclude the Classification**:
- Given that glucose is a 6-carbon sugar (hexose) and contains an aldehyde group (making it an aldose), we can conclude that glucose is an "aldose hexose sugar."

5. **Evaluate the Other Options**:
- The other options provided are "ketose hexose sugar," "pyranose pentose sugar," and "furanose pentose sugar."
- Ketose sugars contain a ketone group (C=O) and are not applicable here since glucose has an aldehyde group.
- Pentose sugars contain 5 carbon atoms, which does not apply to glucose as it has 6 carbon atoms.
- Pyranose and furanose refer to the ring forms of sugars, but since glucose is specifically an aldose hexose, these terms do not apply to the classification of glucose itself.

### Final Answer:
Glucose is an **aldose hexose sugar**.

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