Anatomy And Physiology of GI System. Notes for Nursing Students.

1. PRESENTED BY
Mr. CHETAN.R. SANGATI
FIRST YEAR MSC (N)
DEPT OF MEDICAL SURGICAL NURSING

2. DIGESTIVE SYSTEM

3. INTRODUCATION
• The digestive system is collective name used
to describe the alimentary canal, its accessory
organs and a variety of digestive processes
that tack place at different levels in the canal
to prepare food eaten at the diet for
absorption. The alimentary canal that start at
mouth passes through the thorax ,abdomen
and pelvis and ends at the anus.

4. ORGANS OF THE DIGESTIVE SYSTEM
• ALIMENTARY CANAL is also know as
gastrointestinal tract, which commences at
the mouth and terminates at the anus and
they various parts are given separate names.
MOUTH
PHARYNX
OESOPHAGUS
STOMACH

5. SMALL INTESTINE AND LARGE INTESTINE.
RECTUM AND ANAL CANAL

6. ACCESSORY ORGANS
• Three pairs of salivary glands
• The pancreas
• The liver and bleary tract.

7. MOUTH
ORAL CAVITY
• Anti- by the lip
• Posti- continous with
oropharynx
• Late-by muscle of the
cheeks
• Supi-by bony heard palate
and muscular soft palate.
• Infe-by musculor tongue
and soft tissues of the floor
of the mouth
View of mouth

8. TONGUE
• The tongue is muscular structure that occupies the floor of the mouth.
• It is attached by base to the hyoid bone and fold by mucous membrane
covering ,called the fraenulum, to the floor of the mouth.
• The superior surface consists of stratified squamnous epithelium, with
numers papillae.

9. Blood supply
• Arterial blood supply- external carotid artery.
• Venous drainage- by internal jugular vain.
• FUNCTION OF TONGUE.
 Chewing
Swallowing
Speech
Taste.

10. Teeth
• The teeth are embedded in the alveoli or
sockets of the mandible and maxilla.
• The babies will born with two sets
• One is temporary or deciduous
• Permanent teeth.

11. Function of teeth
• Incisors and canine teeth are the cutting teeth
• And used for biting off pieces of food.
• Premolar and molar teeth with broad ,flat
surface are used for chewing food.

12. Structure of teeth
• The crown-protrudes from the gum
• The root-embedded in the bone
• The neck-slightly narrow region where the
crown merges with the root.
• BLOOD SUPPLY-
 arterial blood supply by maxillary arteries.
Venous drainage by internal jugular vein.

13. Nerve supply
• Upper teeth by branch of maxillary nerves
• Lower teeth by mandibular nerves. Theses
both are from trigeminal nerve.

14. Salivary gland
• Salivary glands release their secretion into
ducts that lead to the mouth.
• There are three main pairs-
The parotid gland
Submandibular gland
Sub lingual gland.

15. Structure of salivary gland
• The gland are surrounded by fibrous capsule
• They consist of a number of lobules made up
of small acini lined with secretory cells.

16. • BLOOD SUPPLY
Aterial blood supply by carotid arteries
Venous drainage into the external jugular
veins.

17. Composition of saliva
• About 1.5 litres of saliva will produce daily.
Witch consist of
 Water
 Mineral salts
 A digestive enzyme –salivary amylase
 Mucus
 Lysozyme
 Immunoglobulines
 Blood clotting factors.

18. Function of saliva
• Lubrication of food
• Cleaning and lubricating the mouth
• Non-specific defence
• taste

19. Pharynx
• The pharynx witch is divided into three parts .
• Nasopharynx
• Oropharnyx
• Laryngopharynx
• Nosopharynx is helps for respiration and oro
nad laryngopharynx are common to the
respiration and GI system.

20. Blood supply
• Arteries supply by facial arteries
• Venous drainage is into facial veins and
internal jugular veins.
• NERVE SUPPLY
Parasympathetic nerve supply by gloss
pharyngeal and vagus nerve.
Sympathetic from the cranial ganglia.

21. Anatomical structure of pharynx

22. oesophagus
• Size-25 cm long
• Diameter-2cm
• Location-
Antiroll- median plane in the thorax
Posterior-vertebral column behind the trachea
and heart.
Supirioly-continous with pharynx
Inferiorly-it joints to the stomach.

23. Blood supply
• Arterial-paired oesophageal arteries.
• Venous drainage-from thoracic region venous
draingeis into the azygos and hemiazygos.
• Function of oesophagus
formation of a bolus
swallowing

24. Structure of oesophagus

25. Stomach

26. • The stomach is a J-shaped dilated
portion of the alimentary tract
situated in epigastria ,umbilical and
left hypochondriac region of the
abdominal cavity.

27. Organ associated with the stomach
• Anteriorly-left lobe of liver and anterior abdominal wall
• Postiriorly-abdominal arota,pancreas,spleen,left kidney,and
adrenal gland.
• Inferiorly-transverses clon and small intestine
• To the left-diapharm and spleen
• Th the right- liver and duodenum
• Superiorly-diaphargm,oesophagusand left lobe of liver.

28. Blood supply
• Arterial supply-by left gastric artery and the
right gastric artery and the gastroepiploic
arteries..
• Venous drainage-portal vein.

29. Function of gastric juice
• Water futher liquefies the food
• Hydrochloric acid-
 acidifies the food and stope the action of salivary amylase
 Kills ingested microbes
 Pepsinogens are activated to pepsins
 Intrensic factors are necessary for the absorpation of
viatamin B12 .

30. Function of stomach
• Temporary storage allowing time for the
digestive enzymes , pepsins to act
• Chemical digestion
• Mechanical breack down
• Limited absorpation of water,alcohol nad
some lipid soluble drugs
• Non specific defence against microbes

31. Small intestine

32. • The small intestine is continous with the
stomach at the pyloric sphincter.the small
intestine is a little over 5 meter long and leads
into the large intestine at the ileocaecal valve.
• BLOOD SUPPLY
• Superior mesentric artery supplies the whole
of the small intestine,
• Venous drainage is by the superior mesentric
vein.

33. Intestinal juice
• About 1500 ml of intestinal juice are secreated
daily by the galnds of small intestine .it
consiste of
• Water
• Mucus
• Mineral salts
• Ph of intestine juice is usually between 7.8
and 8.

34. Function
• Peristalisis movement
• Secreation of intestinal juice
• Competion of chemical digestion of
carbohydrate ,protine,fates.
• Antimicrobial cation
• Secrtion of the hormones cholecystokinin

35. Large intestine
• It is about 1.5 cm long and beginning at the
caecum in the right iliac fossa and terminating
at the rectum and anal canal deep in the
pelvis.
• For discriptive purpose witch divided into
caecum,colon,sigmoid colon,rectum and anal
canal.

36. Structure of large intestine

37. Blood supply
• Arterial supply – by supirior an d inferior
mesentric arteries
• Venous drainage- by supirior and inferior
mesentric veins.

38. functions
• Absorption
• Microbial activity
• Mass movement
• Defaection

39. pancreas
• Colour-pale grey gland
• Weight-60grams
• Length-12-15cm long
• Location-epigastric nad left hypochondriac
regions of the abdominal cavity.

40. Its divided in to two type
• Exocrine pancreas
• Endocrine pancreas
• blood supply
The spleen and mesentirc artery
Venous drainage by portal vein.

41. liver
• Liver is the largest gland in the body.
• Weight is about 1to2.3kg.

42. ORGEN ASSOCITED WITH LIVER
• SUPIRIORLY AND ANTIRIOR- diaphragm and
anterior abdominal wall.
• INFERIORLY- stomach,bile ductus,duodenum
right kidney and adrenal gland.
• Postiriorly- oesophagus,inferior vena cova,
arota, gall bladder,vertebral colum
• Laterally-lower ribs and diaphram.

43. Blood supply
• Hepatic artery and the portal vein tack blood to
the liver.
• Venous return is by number of hepatic veins
FUNCTIONS OF LIVER
Carbohydrate metabolism
Fat metabolism
Protien metabolism
Break down of erythrocytes and defence against
microbes.

44. • Detoxification of druges and toxic substances
• Inactivation of hormones
• Production of heat
• Secretion of bile
• stroge

45. GALL BLADDER
• It is a pear-shaped sac attached to the
postirior surface of the liver by connective
tissue

46. FUNCTION OF GALL BLADDER.
• Reservoir for bile
• Release of stored bile.