Of the following layers which one forms rugae in stomach and villi in intestine of humans?

Options

A. Serosa
B. Sub-mucosa
C. Mucosa
D. Muscularis

Answer

To answer the question regarding which layer forms rugae in the stomach and villi in the intestine of humans, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Layers of the Digestive Tract**: The human digestive tract consists of four main layers:
- Serosa (outermost layer)
- Muscularis (muscle layer)
- Submucosa (connective tissue layer)
- Mucosa (innermost layer)

2. **Understand the Functions of Each Layer**:
- **Serosa**: Provides protection and structure; does not play a role in digestion or absorption.
- **Muscularis**: Responsible for the movement of food through peristalsis; does not form rugae or villi.
- **Submucosa**: Contains blood vessels and nerves; supports the mucosa but does not form rugae or villi.
- **Mucosa**: The innermost layer that directly interacts with the contents of the digestive tract. It is responsible for secretion of digestive enzymes and absorption of nutrients.

3. **Define Rugae and Villi**:
- **Rugae**: These are folds in the mucosa of the stomach that allow for expansion when food enters.
- **Villi**: These are small, finger-like projections found in the mucosa of the small intestine that increase the surface area for absorption.

4. **Determine Which Layer Forms Rugae and Villi**:
- Since both rugae and villi are formed from the mucosa layer, we conclude that the mucosa is responsible for both structures.

5. **Select the Correct Option**: Based on the analysis, the correct answer is **C. Mucosa**.

### Final Answer:
The layer that forms rugae in the stomach and villi in the intestine of humans is the **mucosa**.

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