Midterm paper

MODULE 10 LO1 Digestive System: Small Intestine Histology Dr. Lisa Brinn [email protected]

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Small Intestine • Tract:

A. Duodenum B. Jejunum C. Ileum

• Histology: v Mucosa

o Plicae Ø Villi

§ Microvilli Ø Lacteals

v Submucosa v Muscularis externa

o Longitudinal muscle o Circular muscle

v Serosa • Nervous plexus

v Myenteric plexus v Submucosal plexus

A. Duodenum • 8-10 inches long • Contains duodenal glands

v Brunner’s glands o Produce:

Ø Mucus Ø Buffers

B. Jejunum • 8 feet long • Largest quantity of plicae and villi

v ↑ Absorption

C. Ileum • 10 feet long • Aggregated lymphoid nodules

v Peyer’s patches v Located near ileocecal valve

Lab Models