Tick mark the false statement.

Options

A. Artificial silk is a polysaccharide
B. Natural silk is a protein
C. Collagen protein forms intercellular ground substance
D. Plant proteins are first class proteins

Answer

To determine which statement is false, let's analyze each statement one by one:

1. **First Statement**: "Artificial silk is a polysaccharide."
- **Analysis**: Artificial silk, also known as rayon, is derived from cellulose, which is indeed a polysaccharide. Therefore, this statement is **true**.

2. **Second Statement**: "Natural silk is protein."
- **Analysis**: Natural silk is produced by silkworms and is primarily made of fibroin, which is a protein. Thus, this statement is **true**.

3. **Third Statement**: "Collagen is a protein from intercellular ground substance."
- **Analysis**: Collagen is indeed a protein that is found in the extracellular matrix, which is often referred to as the intercellular ground substance. Hence, this statement is **true**.

4. **Fourth Statement**: "Plant proteins are first-class proteins."
- **Analysis**: First-class proteins (or complete proteins) contain all essential amino acids and are typically found in animal sources. Plant proteins are generally considered second-class proteins because they may lack one or more essential amino acids. Therefore, this statement is **false**.

Based on the analysis, the false statement is:

**Answer**: Plant proteins are first-class proteins (Statement 4).

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