The incorrect statement among the following is:

Options

A. `alpha`-D-glucose and `beta`-D-glucose are anomers.
B. `alpha`-D-glucose and `beta`-D-glucose are enantiomers.
C. Cellulose is a straight chain polysaccharide made up of only `beta`-D-glucose units.
D. The penta acetate of glucose does not react with hydroxyl amine.

Explanation

To determine the incorrect statement among the provided options regarding biomolecules, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement 1: Alpha D-Glucose and Beta D-Glucose are anomers.**
- **Analysis**: Anomers are a type of stereoisomer that differ at the anomeric carbon, which is the carbon that was the carbonyl carbon in the open-chain form. Alpha and beta forms of glucose differ in the orientation of the hydroxyl group (-OH) at the anomeric carbon. Therefore, this statement is **correct**.

2. **Statement 2: Alpha D-Glucose and Beta D-Glucose are enantiomers.**
- **Analysis**: Enantiomers are a specific type of stereoisomer that are non-superimposable mirror images of each other. Alpha and beta D-glucose are not mirror images; they are anomers. Thus, this statement is **incorrect**.

3. **Statement 3: Cellulose is a straight-chain polysaccharide made up only of Beta D-Glucose units.**
- **Analysis**: Cellulose is indeed a polysaccharide composed exclusively of beta-D-glucose units linked by 1,4-glycosidic bonds. Therefore, this statement is **correct**.

4. **Statement 4: Penta acetate of glucose does not react with hydroxyl amine.**
- **Analysis**: The penta-acetate form of glucose does not have a free aldehyde group, which is necessary for a reaction with hydroxyl amine. Therefore, this statement is **correct**.

### Conclusion:
The incorrect statement among the options is **Statement 2**: "Alpha D-Glucose and Beta D-Glucose are enantiomers."