Transcript Digestive system1

Digestive system
Mouth
Oral cavity, lips, lateral wall is the cheek,
roof is hard and soft palate,
Uvula is fleshy fingerlike projection of soft
palate.
Vestibule is the space between cheek, and
teeth.
Lingual frenulum a fold of mucous
membrane prevent the tongue from
falling back
Tongue tie short frenulum
Esophagus
Run from the pharynx to stomach
Is 25cm in length?
Enter abdomen through esophageal
opening of the diaphragm at level of
T10.
Stomach
Is C shaped, lie in epigastric, and left
hypochondrium.
25 cm long
It has greater curvature, and lesser curvature
The mucous membrane has folds called rugae
Lesser omentum is a double layer of peritoneum
from liver to lesser curvature
Greater omentum another double layer drapes
down and cover the abdominal organs, it is
riddled with fat which insulate, cushion and
protect abdominal organs
Has large collection of lymph nodes
Cardia: contain sphincter
through which food enter
stomach
Fundus: the part to the left
and above the cardia
Body: between fundus and
pylorus
Pylorus: terminal stomach
ends in pyloric sphincter.
Small intestine
Is muscular tube from pyloric sphincter
to ileocecal valve?
It is 4 meter in length in living person.
Attached to posterior abdominal wall by
mesentery
Small intestine is divided into
Duodenum
Jejunum
Ileum
Duodenum: is 25 cm in length,
C shaped surround head of pancreas
It is divided into four parts
Bile duct join pancreatic duct to open in major
duodenal papilla in posterio-medial par of 2nd part
of D just below middle
Jejunum: is 2.5 meter
Ileum: is3.5 meter ends in ileocecal valve
Peyer’s patches local collection of lymphatic in SM.
Duodenum
Gallbladder
Thin wall sac; lie in inferior surface
of liver
Concentrate, and store 50cm of bile.
Cystic duct open in to common
hepatic duct to form bile duct
Biliary colic
Acute cholecystitis
Large intestine
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Is 1.5 meter in length?
Extend from ileocecal valve to anus
Much larger in diameter
Divided in to
Caecum,Appendix,Colon,Rectum
• Anal canal.
Colon is divided into
Ascending, transverse,descending,
Sigmoid colon.
• Appendix: Narrowest part of the
alimentary canal, worm like tube.
• Arise from caecum 2 cm below ileocaecal junction.
• Length is variable from 1.5 cm to 22cm.
• Position is extremely variable, so
symptoms of appendicitis may vary.
Colon
• Teniae coli represent outer longitudinal
muscle layer of colon,3 in number.
• TC start at base of appendix and end at
rectosigmiod junction
• Hustration because teniae is shorter than
colon by one foot
• Appendices epiplocie condensation of
fat, hanging from bowel wall.
Rectum:
The last 15 cm of the
colon
Has three lateral flexions
LT,RT,LT.
Rectum is divided into
upper third, middle
third and lower third.
Anal canal: length is 4cm.
Have two sphincters
Internal is involuntary, formed of
smooth muscle fibers
External is voluntary formed of
striated muscle fibers
• Piles: is dilatation of veins may be
either internal or external
• Fissure: tear in anal mucosa
severely painful
• Abscess may lead to fistula
Liver and gallbladder
Largest organ in the body,
weight is 1.5kilo.
Liver has three surfaces
,superior,posterior,and
inferior
The umbilical fissure and
falciform ligament
divide antro- superior
surface into RT and left
lobes
• RT lobe of liver surgically is divided
into segment V, VI ,VII, VIII.
• LT lobe is divided into II, III, IV
• Segment I is caudate lobe of liver
• Lie in RT hypochondrium
• Produce bile, leave liver through
RT, LT hepatic ducts, join cystic
duct to form bile duct
Blood supply
Portal vein70%, hepatic artery 30%
Bile duct, join pancreatic duct to
open in major duodenal papilla in
2nd part of duodenum.
Pancreas
Triangular in shape
Head, neck, body, and tail.
Extend from duodenum to
spleen
Lie retro peritoneal
Lie in epigastric region
Mixed gland with endocrine
and exocrine function
Have two ducts which join
bile duct and open in
2nd part of duodenum
Pancreatitis
Salivary glands
Three pairs of salivary glands
Parotid gland
• Lie behind the lobule of the ear
• The largest salivary gland
• Two lobes ,one large the superficial,
one small, the deep lobe
• Has duct open in the mouth,
opposite upper 2nd molar tooth
Submandibular gland
• Lie below angle of the mandible
• Duct opens in floor of the
mouth, opposite to frenulum of
tongue
Small sublingual gland
• Under the tongue
Mucosa,,submucosa,,,musculosa,,serosa
Structure of digestive tube
Epithelial lining of digestive tube
Non-keratinized st.sq.epithelium
• Oral cavity
• Esophagus
• Anal canal
Simple columnar epithelium
• Stomach,,,,,rugae
• Small intestine…..folds,villi,microvilli(the combination of the folds of
Kerckring(valvulae conniventes), the villi, and the microvilli increases the
total absorptive area of the mucosa perhaps 1000-fold, making a
tremendous total area of 250 or more square meters for the entire small
intestine.
• Large intestine…..no villi