Скачать или смотреть Digestive Tract anatomy |NRE1 and USMLE1|by dr Hidayat|part9

Topic: Digestive Tract Anatomy — Layers of Gut Wall |MSMS|
Exam Focus: NRE-1 |FMGE |USMLE Step 1
Prepared by: Dr Hidayat
This video explains the layers of the gastrointestinal tract wall, following the First Aid for USMLE Step 1 framework. The lecture integrates microscopic structure, nerve plexuses, and clinical correlations that appear in tricky NRE-1 and Step 1 MCQs.
The gut wall is organized from inside to outside as MSMS — Mucosa, Submucosa, Muscularis externa, Serosa.
Mucosa: composed of the epithelium, lamina propria, and muscularis mucosa; main site for absorption and secretion.
Submucosa: contains the Meissner |submucosal|plexus, glands, vessels, and connective tissue that regulate secretory activity.
Muscularis externa: formed by inner circular and outer longitudinal muscle layers; the Auerbach (myenteric) plexus lies between them and controls motility.
Serosa |Adventitia: outermost covering — serosa when intraperitoneal, adventitia when retroperitoneal.
Ulcers may penetrate through the submucosa or muscular layers, while erosions remain limited to the mucosa.
The basal electrical rhythm originates in the interstitial cells of Cajal, setting peristaltic frequency:

💡 High-Yield Clinical Points
Damage to the Auerbach plexus → Achalasia (failure of LES relaxation).
Meissner plexus dysfunction affects secretion and blood flow.
Ulcers vs. Erosions often tested in NRE-1 and Step 1 exams.
Disorders of interstitial cells of Cajal cause intestinal dysmotility.
Perfect For
NRE-1 and FMGE candidates mastering GI anatomy
USMLE Step 1 students reviewing First Aid histology diagrams
MBBS students strengthening system-wise understanding
Hashtags
#DigestiveTractAnatomy #GastrointestinalAnatomy #FirstAid #NRE1 #USMLEStep1 #FMGE #DrHidayat #GutWallLayers #MSMS #MedicalEducation #HighYield #ExamPrep #Anatomy