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Histology

Digestive System:

Anatomy & Histology of the Alimentary Canal

Cross section of the digestive tract

http://www.argosymedical.com/flash/digestion/landing.html

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I). Layers of the Digestive Tract

A. Peritoneum:

B). Mesentery

C). Mucosa

D). Submocousa

E). Muscularis

F). Serosa:

 

II). Smooth Muscle

Jejunum Section
http://www.lab.anhb.uwa.edu.au/mb140/CorePages/Muscle/Muscle.htm

Innervated: autonomic nervous system.

Longitudinal and circular muscle layer orient at right angles to each other.

                    rhythmic contraction called peristalsis.

Peristalisis

III). Alimentary Canal:

Breaks down food and absorbs nutrients

Digestive Tract
 
Alimentary Canal

 

 

A). Mouth or Oral Cavity or Buccal Cavity

Mouth

1). Lips and cheeks

2). Palate:

a). Hard Palate:

b). Soft Palate

Accessory Digestive Organ

(tongue, teeth, salivary glands)

3). Tongue

Tongue

Manipulates food forming bolus

Interlacing bundles of skeletal muscles

Sense organs

4). Salivary glands

Salivary Glands

a). Buccal glands

b). Parotid gland

c). Submandibular gland

d). Sublingual gland

 

5). Teeth

Adult Teeth

 

a). 2 sets

 primary teeth

secondary set consists of 32 teeth

Incisors:

Central Incisor

Lateral Incisor

Cuspid (canine):

Bicuspid premolar;

First Molar

Second Molar

Third (wisdom teeth)

Tooth Structure

b). Tooth Structure

Crown

Gum (gingival)

Enamel

Cells that develop the enamel degenerate when the tooth erupts thus there are none available for repair.

Root

Dentin

B). Pharynx

Pharnyx Pharnyx Histology

C). Esophagus

Collapses when not needed and mucosa folds.

Passes the diaphragm at the esophageal hiatus

 

D). Stomach

Stomach

1). Cardiac Region

with the cardiac sphincter

2). Fundus

3). Body

  • Lesser curve
  • Greater curve

4). Pylorus

connected to the small intestine by the pyloric sphincter

5). Rugae of mucosa

6).  Blood Vessels

Left and Right Gastric Arteries
(come from the celiac artery)
Also serves the esophagus
 
Left and Right Gastric Veins
(drain into the inferior vena cava)
 

7). Histolgoy

Gastric pits

Histolgoy of the Stomach

http://webanatomy.net/histology/digestive/digestive_index.htm

 

E). Small Intestine

Extends from pyloric sphincter to the ileocecal valve of large intestine.

1). Regions

i). Duodenum

(25 cm)

ii). Jejunum

(2.5 m)

iii). Ileum

(3.6 m)

 

Small Intestine
Mnemonic:

Dow Jones Industrial
Duodenum
Jejunum
Ileum

http://www.uclan.ac.uk/facs/health/nursing/sonic/scenarios/scenario1GITlecture.htm

2). Histology

i). Villi and microvilli  

ii).  Peyer’s patches

Small Intestine Histology Small Intestine
http://www.mhhe.com/biosci/ap/histology_mh/simpleep.html http://www.lab.anhb.uwa.edu.au/mb140/CorePages/Lymphoid2/lymph2.htm

F). Large Intestine

  ileocecal valve to the anus.

1). Gross anatomy

i). Teniae coli: 

ii). Haustra

iii) Epiploic appendages

Large Intestine

2). Subdivisions

i). Cecum

ii). Appendix

iii). Colon

a). Ascending Colon

b). Transverse Colon

c). Descending Colon

d). Sigmoid Colon

iv). Rectum

v). Anal Canal

Anal Sphincters

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Rectum
3. Histology

Goblet cells

 

Mucosa layer

 

Submucosa layer

Smooth muscle layer

 

Histology
http://biodidac.bio.uottawa.ca/thumbnails/histocatquery.htm

 

4.  Vessels of the small & large intestine

Arteries

Digestive Arteries

i.   Common hepatic artery

ii.   Superior mesenteric artery

iii.  Inferior mesenteric artery

 

Veins

Veins of the Digestive System

i.  Superior mesenteric vein

ii. Inferior mesenteric vein

iii.  Splenic vein from the spleen

iv.  Hepatic portal system