Bacteria can be classified into two groups on the basis of

Options

A. difference in the chemical composition of cell wall
B. staining reaction
C. mode of nutrition
D. both 1 and 2

Answer

To classify bacteria into two groups, we can follow these steps:

### Step 1: Understand the Basis of Classification
Bacteria can be classified based on various characteristics, but the most common methods are based on the chemical composition of the cell wall and staining reactions.

### Step 2: Identify the Two Major Groups
1. **Gram-positive Bacteria**: These bacteria have a thick peptidoglycan layer in their cell wall, which retains the crystal violet stain used in the Gram staining procedure.
2. **Gram-negative Bacteria**: These bacteria have a thinner peptidoglycan layer and an outer membrane, which does not retain the crystal violet stain but takes up the counterstain (usually safranin).

### Step 3: Consider Staining Reactions
Bacteria can also be classified based on their reaction to staining techniques:
- **Cocci**: These are spherical bacteria.
- **Bacilli**: These are rod-shaped bacteria.

### Step 4: Conclusion
Thus, bacteria can be classified into two groups based on:
1. Differences in the chemical composition of the cell wall (Gram-positive and Gram-negative).
2. Staining reactions (Cocci and Bacilli).

### Final Answer
The correct answer is that bacteria can be classified into two groups based on both the chemical composition of the cell wall and the staining reactions.

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