Which of the following statement is incorrect w.r.t. histology of alimentary canal?

Options

A. Serosa is the outermost layer made up of a thin mesothelium with some connective tissue
B. Muscularis layer is formed by smooth muscles usually arranged into an inner longitudinal layer and outer circular layer
C. Submucosal layer is formed of loose connective tissue
D. An oblique muscle layer may be present in stomach

Answer

To determine which statement is incorrect with respect to the histology of the alimentary canal, we need to analyze the layers of the alimentary canal and their characteristics. Here’s a step-by-step breakdown:

### Step 1: Understand the Layers of the Alimentary Canal
The alimentary canal consists of four main layers from the outermost to the innermost:
1. **Serosa**: The outermost layer, made up of connective tissue and mesothelium.
2. **Muscular Layer**: Composed of two layers of smooth muscle:
- **Outer Longitudinal Muscles**
- **Inner Circular Muscles**
3. **Submucosa**: A layer of connective tissue that contains blood vessels, nerves, and glands.
4. **Mucosa**: The innermost layer that lines the lumen of the alimentary canal.

### Step 2: Analyze Each Statement
Now, let's evaluate the statements provided in the question:

1. **Serosa is the outermost layer**: This statement is **correct**.
2. **Muscular layer is formed by smooth muscles arranged into inner longitudinal and outer circular**: This statement is **incorrect**. The arrangement is actually outer longitudinal and inner circular.
3. **Submucosal layer is formed from loose connective tissue**: This statement is **incorrect**. The submucosa is typically made of dense connective tissue.
4. **Oblique muscle layer may be present in the stomach**: This statement is **correct**. The stomach does have an additional oblique muscle layer.

### Step 3: Identify the Incorrect Statements
From the analysis:
- The second statement regarding the arrangement of the muscular layer is incorrect.
- The third statement regarding the composition of the submucosal layer is also incorrect.

### Conclusion
The statements that are incorrect with respect to the histology of the alimentary canal are the second and third statements.