DIGESTIVE SYSTEM

1
DIGESTIVE SYSTEM

• Through stomach

2
(No Transcript)
3
Overall Digestive Process

• Ingestion
• Movement
• Digestion (mechanical chemical)
• Absorption (into blood/lymph vessels)
• Elimination Defecation

4
GI Organization

• Digestive tract canal
• Gastrointestinal tract
• Alimentary canal
• Accessory Structures outside of the tract

5
(No Transcript)
6
Microstructure - general

• Mucosa
• Mucous membrane
• May have villi and microvilli
• Submucosa
• Very vascular
• Muscularis
• Serosa Visceral Peritoneum

7
(No Transcript)
8
Peritoneum

• Parietal peritoneum
• Visceral peritoneum
• Peritoneal cavity

9
(No Transcript)
10
Folds of Peritoneum

• Binds organs together, anchors them, suspends
  vessels
  
• Mesentery proper (SI-Dorsal BW)
• Mesocolon Mesorectum (LI-Dorsal BW
• Falciform ligament (Li-Ventral BW)
• Lesser omentum (Lesser curvature/duodenum-Li)
• Greater omentum (Greater curvature-Dorsal BS

11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
Oral Cavity

• Labia
• Labial frenulum
• Hard palate
• Soft palate
• Uvula

15
(No Transcript)
16
Tongue (accessory)

• Glosso-
• Lingu-
• Skeletal muscle covered by mucous membrane
• Lingual frenulum

17
(No Transcript)
18
Tongue

• Papillae
• Taste Zones
• Sweet, Salt
• Sour, Bitter
• Function
• Bolus formation

19
(No Transcript)
20
Salivary Glands (accessory)

• Parotid
• Submandibular
• Sublingual

21
(No Transcript)
22
(No Transcript)
23
Saliva

• 1-1 ½ liters/day
• 99 water
• Mucins
• Amylase
• Lysozyme anti-microbial

24
Saliva Secretion Controls

• Nervous System Medulla oblongata Pons
• ANS
• Smell, thought, sight, irritation
• Dehydration, Fear

25
Teeth (accessory)

• Gingivae
• Crown
• Root
• Neck

26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
Tooth Components

• Periodontal ligament
• Dentin
• Pulp cavity pulp
• Apical foramen
• Enamel
• Cementum

30
(No Transcript)
31
Teeth

• Deciduous 20
• Permanent - 32

32
(No Transcript)
33
Teeth - shape

• Incisor
• Canine
• Premolar
• Molar

34
(No Transcript)
35
Dental Terminology

• Labial
• Buccal
• Lingual
• Palatal
• Occlusal

36
Digestion in Oral Cavity

• Ingestion
• Mastication
• Chemical digestion
• Deglutition

37
Pharynx

• Already did under Respiratory

38
Esophagus

• Hiatus
• Sphincters
• Function
• Peristalsis
• Heartburn is actually esophageal burn

39
(No Transcript)
40
(No Transcript)
41
(No Transcript)
42
(No Transcript)
43
Stomach (gastric)

• Anatomy
• Cardia
• Fundus
• Body
• Pylorus and Pyloric Sphincter
• Greater Curvature
• Lesser Curvature

44
(No Transcript)
45
(No Transcript)
46
Digestion in Stomach

• Stores food
• Chyme
• Motility, Mixing Emptying
• Peristalsis
• To Pyloric Sphincter, to Duodenum
• Pacemaker cells make smooth muscle contract about
  3x/minute when food present

47
(No Transcript)
48
Controls of Stomach Motility

• 2-6 hours to empty
• Controls include volume distention
• GASTRIN
• Hormone released by pyloric cells in response to
  distention. Stimulates gastric motility.
  
• Caffeine stimulates gastrin release

49
Controls of Stomach Motility

• ENTEROGASTRIC REFLEX
• As duodenum distends, it inhibits gastric
  motility
  
• SECRETIN
• CHOLECYSTOKININ
• GASTRIC INIHIBITORY PEPTIDE

50
(No Transcript)
51
Gastric Secretion

• Juice
• Zymogenic Cells make Pepsinogen
• Parietal Cells make HCl
• Alkaline blood following a meal
• Mucus Cells make protective mucus

52
(No Transcript)
53
Controls of Stomach Secretion

• GASTRIN
• Cephalic, Gastric Intestinal phase of seeing
  and eating food
  
• ENTEROGASTRIC REFLEX
• GIP, CHOLECYSTOKININ, SECRETIN

54
(No Transcript)
55
(No Transcript)
56
(No Transcript)
57
Stomach Physiology

• Very little absorption