1. HISTOLOGY OF DIGESTIVE TRACT
By DR SOBIA IBRAHIM
Assistant professor ANATOMY
KEMU

2. PARTS OF DIGESTIVE TRACT
Oral cavity
Tubular part
Associated glands

3. GENERAL STRUCTURE OF GIT
Mucosa:
epithelium,
Lamina propria,
muscularis mucosae
Submucosa:
Connective tissue
with blood & lymph vessels, nerve plexus,
Glands(some places)
Muscularis externa:
Inner circular and
outer longitudinal
Serosa / adventitia:

4. NERVE PLEXUSES Autonomic plexuses Submucosal /Meissner’s
Myenteric /Auerbach’s
Parasympathetic pre&post ganglionic fibres
Sympathetic post ganglionic fibres
Sensory nerve fibres
Parasympathetic ganglia

5. MAIN FUNCTIONS OF MUCOSA
EPITHELIAL LINING
Selectively permeable memb.
Transport & digestion of food
Promote absorption of products of digestion
Produce hormones affecting activity of GIT
Produce mucus for lubrication & protection
LAMINA PROPRIA
Macrophages & lymphoid cells rich zone
Immunoglobulin A (IgA) production
MUSCULARIS MUCOSAE
Promotes movement of mucosa, increasing its contact with food

6. MEDICAL APPLICATION HIRSCHSPRUNG DISEASE (congenital megacolon)
CHAGAS DISEASE (Trypanosoma cruzi infection)
Nerve plexuses severely damaged& neurons destroyed
Disturbance of GIT motility & frequent dilatations of intestines
Effects of emotional stress on GIT

7. ORAL CAVITY

8. LIP Core of lip is skeletal musle embedded in fibroelastic C.T.
Each lip has 3 surfaces:
Cutaneous surface: covered by skin with hair follicles & glands.
Red surface: covered by modified skin. St. squamous non- keratinized which has thick stratum lucidum, making it more translucent. Its dermis is rich in vessels that’s y appear red
Oral surface: S.Q NON- k . Then lamina propria. Labial salivary glands are present in L.P

10. CHEEK Consists of skeletal muscle and fibroelastic tissue
Lined outside by skin of face
Inside by oral mucosa with st. sq non keratinized epith. and lamina propria
Submucosa contains elastic fibres and mixed mucous and serous glands
Thus preventing folding of mucosa and lubrication of mouth.

11. PALATE Hard Soft Hard palate Contain bone
Lined by stratified squamous keratinized epithelium
Lamina propria
Submucosa present in places, contain mucous glands & fat

12. Inferior (oral) surface lined by stratified keratinized epithelium
Soft palate
Inferior (oral) surface lined by stratified keratinized epithelium
Superior (pharyngeal) surface lined by pseudstrafied columnar ciliated epithelium
Lamina propria contains glands
Core made of skeletal muscle

13. TEETH Each has three parts Crown Root Neck
Centre has a cavity called as pulp cavity filled with C.T called as dental pulp.
Cavity extends to the root and opens to exterior via an apical foramen.
Hard tissue- dentin, enamel and cementum.
Soft tissue- pulp, peridontal ligament.