Duodenum

Definition

The duodenum is the first section of the small intestine, immediately following the stomach. It plays a crucial role in digestion and nutrient absorption.

5 Must Know Facts For Your Next Test

1. The duodenum receives partially digested food from the stomach and digestive enzymes from the pancreas.
2. It neutralizes stomach acid through secretions from Brunner's glands.
3. The duodenum is home to a specific microbiota that aids in digestion and protects against pathogens.
4. Bile from the liver and gallbladder enters the duodenum to emulsify fats.
5. The pH level in the duodenum rises to about 6-7 due to bicarbonate ions.

Review Questions

• What role does the duodenum play in digestion?
• How does the microbiota in the duodenum contribute to overall gut health?
• What are two main types of secretions entering the duodenum, and what are their functions?

Related terms

Jejunum:

The middle section of the small intestine, following the duodenum.

Brunner's Glands: Glands located in the duodenum that secrete alkaline mucus to neutralize stomach acid.

Bile Duct: A duct that conveys bile from the liver and gallbladder into the duodenum for fat emulsification.