gastroentestinal anatomy and physiology lecture

GIT LECTURE 1

1. Gastrointestinal
system
Dr jabbar jasim

3. IntroductionIntroduction
1.Composed of GI tract and accessory
organs
2.Breaks down ingested food for use by
the body
3.Digestion occurs by mechanical and
chemical mechanisms
4.Excretes waste products or feces
through process of defecation

5. Topographic DivisionsTopographic Divisions
•
Four-quadrant
topographical
pattern
•Horizontal
–Transumbilical
plane
–Between
intervertebral disc
LIII and LIV
•Vertical median
plane

7. Nine quadrant patternNine quadrant pattern

Horizontal planes
1.Subcostal plane or
transplyloric plane
2.intertubercular plane

Vertical planes
•two Midclavicular plane
1.Epigastric region
2.R/L hypochondrium
region
3.Umbilical region
4.R/L lumbar region
5.Pelvic region
6.R/L inguinal region

8. 1.Ingestion
2.Secretion
3.Mixing and
Propulsion
Motility
4.Digestion
Mechanical
chemical
5.Absorption
6.Defecation

9. Anatomy & Function
(The swallowing wave)

13. PANCREAS
•Produces secretions to aid digestion
1.Head
2.Body
3.Tail
•Pancreatic duct /duct of Wirsung
–Hepatopancreatic ampulla
–Sphincter of the heatopancreatic ampulla
(sphincter of (Oddi)
•Regulates passage of pancreatic juice and bile
•Accessory duct (duct of Santorini)

14. PancreasPancreas

99% is 99% is exocrineexocrine that that
secrets pancreatic juicesecrets pancreatic juice

1% is 1% is endocrineendocrine ( ( islets islets
of Langerhansof Langerhans))
Glucagon ALFA
Insulin BETA
Somatostatin GAMA
Pancreatic Juice
•1200-1500 mL/day
•pH 7.1-8.2
•Sodium bicarbonate
•Enzymes
–Pancreatic amylase
–Trypsin
•Entereokinase
–Chymotrypsin
–Carboxypeptidase
–Elastase
–Pancreatic lipase
–Ribonuclease and
deoxyribonuclease

17. Liver and GallbladderLiver and Gallbladder
•Liver is the largest gland of the body
•Bile is secreted by liver and carried to the gall
bladder for temporary storage.
•Right and left lobe separated by
falciform ligament.
Coronary ligaments
Round ligament (ligamentum teres)

– Remnant of umbilical vein

18. LIVER

20. Blood Blood
supply to supply to
the liverthe liver

22. Liver functionsLiver functions
1.Metabolism of:
a)Carbohydrates
b)Lipids
c)Proteins
2.Process drugs and hormones
3.Excrete bilirubin
4.Synthesize bile salts
5.Storage
a)Glycogen
b)Vtamins
c)Minerals
6.Phagocytosis
7.Activate Vitamin D

23. EsophagusEsophagus
•Narrowest part of GIT after Vermiform appendix.
•Extend from the pharynx( lower border of cricoid
cartilage @ C6) to stomach ( @ T11).
•Consists of 3 parts. Cervical, thoracic (longest) and
abdominal ( shortest ).
•Total length – 25cm
•Pierce the diaphragm at the level of T10 and open
into the cardiac end of stomach at T11.

25. StomachStomach

26. Small intestineSmall intestine
•Adapted for digestion and absorption
•About 6m in length
1.Duodenum
2.Jejunum
3.Ileum
•Ileocecal sphincter
– Connection to large intestine