The incorrect statement regarding cellulose is

Options

A. it is a polymer of D-glucose
B. It has `beta-1,4-` glycosidic linkage
C. it is used for making rayon fibre
D. it can be obtained by polymerisation of D-glucose in the lab.

Answer

To determine the incorrect statement regarding cellulose, let's analyze the provided options step by step:

### Step 1: Understand the Composition of Cellulose
Cellulose is a polysaccharide made up of many units of D-glucose. It is primarily found in the cell walls of plants and is the most abundant organic polymer on Earth.

**Hint:** Remember that cellulose is a polymer made from glucose units.

### Step 2: Identify the Glycosidic Linkage
Cellulose consists of β(1→4) glycosidic linkages between the glucose units. This means that the first carbon of one glucose molecule is linked to the fourth carbon of another glucose molecule through a beta linkage.

**Hint:** Focus on the type of glycosidic linkage in cellulose.

### Step 3: Source of Cellulose
Cellulose is exclusively found in plants. It is a major component of the plant cell wall and contributes to the structural integrity of plants.

**Hint:** Consider where cellulose is primarily located in nature.

### Step 4: Laboratory Synthesis of Cellulose
It is important to note that cellulose cannot be synthesized in a laboratory setting due to the complexity of its structure and the requirement for multiple glucose units to form the polymer.

**Hint:** Think about the feasibility of synthesizing complex natural polymers in a lab.

### Step 5: Evaluate the Options
Now, let’s evaluate the statements:
- **Option A:** You get D-glucose from all units upon hydrolysis - This is correct.
- **Option B:** Cellulose is made from many units of glucose - This is correct.
- **Option C:** Cellulose is mainly found in plants - This is correct.
- **Option D:** We cannot prepare cellulose in the lab - This is incorrect.

### Conclusion
The incorrect statement regarding cellulose is **Option D**: "We cannot prepare cellulose in the lab."

**Final Answer:** Option D is the incorrect statement.

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