Learning Target

By the end of this station, the student should be able to:

1. Identify the duodenum slide using villi, intestinal glands, and Brunner’s glands.
2. Relate the microscopic features of duodenum to absorption, secretion, and neutralization of acidic chyme.

Required Material

• Prepared histology slide of duodenum
• Light microscope
• Pointer / labeled slide image if available
• Answer sheet / checklist
• Pencil or pen

Student Task / Procedure

1. Focus the slide under low power.
2. Identify the mucosa and finger-like intestinal villi.
3. Observe the intestinal glands / crypts between the villi.
4. Look for Brunner’s glands in the submucosa.
5. Identify the muscular layer if visible.
6. State one functional importance of Brunner’s glands.

Observation / Identification Points

Students should identify:

• Mucosa with finger-like villi
• Simple columnar epithelium with goblet cells
• Lamina propria inside villi
• Intestinal glands / crypts of Lieberkühn
• Muscularis mucosae
• Submucosa containing Brunner’s glands
• Muscularis externa with inner circular and outer longitudinal layers
• Absence of Peyer’s patches as a major feature

Result / Interpretation

The slide is identified as duodenum.

The duodenum shows intestinal villi for absorption and intestinal glands for secretion. The most important identifying feature is the presence of Brunner’s glands in the submucosa. These glands secrete alkaline mucus, which protects the mucosa and helps neutralize acidic chyme coming from the stomach.

Viva Questions

1. What is the most important identifying feature of duodenum?
Brunner’s glands in the submucosa.

2. What is the function of intestinal villi?
They increase surface area for absorption.

3. What type of epithelium lines the duodenum?
Simple columnar epithelium with goblet cells.

4. What are crypts of Lieberkühn?
They are intestinal glands present between the villi.

5. What is the function of Brunner’s glands?
They secrete alkaline mucus to protect the duodenal mucosa and neutralize acidic chyme.

Marking Scheme

Total Marks: 5

Common Student Mistakes

• Confusing duodenum with jejunum by focusing only on villi.
• Forgetting that Brunner’s glands are present in submucosa.
• Confusing Brunner’s glands with intestinal glands / crypts.
• Missing the functional link: alkaline mucus protects against acidic chyme.

AIM Feedback

To identify duodenum correctly, first look for intestinal villi. Then confirm the slide by finding Brunner’s glands in the submucosa. Remember: villi support absorption, intestinal glands support secretion, and Brunner’s glands protect the duodenum by secreting alkaline mucus. In viva, always connect the microscopic feature with its function.