The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx –...
-
Upload
sophie-johnson -
Category
Documents
-
view
226 -
download
1
Transcript of The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx –...
![Page 1: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/1.jpg)
The Digestive System
![Page 2: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/2.jpg)
Organ groups of digestion
• Alimentary organs– Mouth– Pharynx– Esophagus– Stomach– Small and large
intestine
• Accessory digestive organs– Teeth and tongue– Liver– Pancreas– Salivary glands– gallbladder
![Page 3: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/3.jpg)
The processes of digestion
• Ingestion
• Secretion
• Mixing and propulsion
• Mechanical and chemical digestion
• Absorption
• Defecation
![Page 4: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/4.jpg)
Peristalsis and segmentation
• Peristalsis
![Page 5: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/5.jpg)
Layers of the GI tract
• Mucosa– Layer of
epithelium – Lamina propria
(connective tissue)
– Thin layer of smooth muscle (muscularis mucosae)
• Submucosa• Muscularis• Serosa
![Page 6: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/6.jpg)
ANS input
• Vagus nerve supplies parasympathetic input to most parts of the GI tract.
• Preganglionic parasympathetic neurons synapse on postsynaptic neurons in the submucosal and myenteric plexuses.
• Parasympathetic stimulation increases motility and GI secretion.
• Sympathetic postsynaptic neurons in the plexuses decrease GI section and decrease motility by inhibiting neurons of ENS
![Page 7: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/7.jpg)
![Page 8: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/8.jpg)
![Page 9: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/9.jpg)
Mouth
• Buccal cavity• Oral mucosa• Vestibule• Gingivae• Hardpalate• Soft palate• Uvula
![Page 10: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/10.jpg)
Salivary glands• Cleanse
mouth• Dissolve
food chemicals
• Moisten food
• Enzymes break down carbs
![Page 11: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/11.jpg)
Teeth
• Crown, neck and root
• Peridontal ligament
• Enamel• Dentin• Root canal
![Page 12: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/12.jpg)
Tooth varieties
Incisors
Cuspids
Bicuspids
Molars
Mastication Bolus
![Page 13: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/13.jpg)
Tongue
![Page 14: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/14.jpg)
Swallowing• Deglutition
• 3 phases– Buccal– Pharyngeal– Esophogeal
• Peristalsis– Secondary
peristaltic waves
![Page 15: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/15.jpg)
Deglutition
![Page 16: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/16.jpg)
Stomach• Fundus
• Body
• Pylorus– Pyloric
sphincter
• Rugae
![Page 17: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/17.jpg)
Stomach histology
![Page 18: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/18.jpg)
Gastric Glands
• Mucous cells– Surface & neck
• G cells
• Parietal cells
• Chief cells
• Enteroendocrine cells
![Page 19: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/19.jpg)
Stomach and chemical digestion
Cephalic (Reflex) phase– Triggered by sensory signals surrounding food.– Activates vagal nerve and ANS to enhance
secretions
– Hydrochloric Acid Production in Parietal Cells
![Page 20: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/20.jpg)
Stomach and chemical digestion
Gastric Phase– Activation of local myeteric reflexes
and vagovagal reflexes– Gastrin– Release of HCl from parietal cells
![Page 21: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/21.jpg)
Stomach and chemical digestion
• Intestinal Phase– Excitatory component– Inhibitory component
![Page 22: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/22.jpg)
Gastric Secretion: 3 Phases
![Page 23: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/23.jpg)
Stomach and mechanical digestion
• Stomach filling• Contractile activity– Peristalsis
• Gastric emptying
![Page 24: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/24.jpg)
Small intestine and associated organs
![Page 25: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/25.jpg)
Small intestine histology
![Page 26: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/26.jpg)
Small intestine histology
![Page 27: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/27.jpg)
Liver
• Digestive function is to produce bile.• Metabolic function is to process
venous blood from digestive tract• Functional unit is a lobule
![Page 28: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/28.jpg)
Liver
![Page 29: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/29.jpg)
Liver Functions
• Carbohydrate metabolism• Lipid metabolism• Protein metabolism• Processing of drugs and hormones• Excretion of bilirubin• Synthesis of bile salts• Storage• Phagocytosis• Activation of vitamin D
![Page 30: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/30.jpg)
Cholesterol
![Page 31: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/31.jpg)
Accessory organs
![Page 32: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/32.jpg)
Bile
• Alkaline solution that includes bile salts, phospholipids and electrolytes.– Bile salts derived from cholesterol
• Bile salts emulsify fats and solubilize cholesterol, increasing absorption.
• Bile is recycled• Fatty chyme and bile returning to liver
stimulates more production of bile.
![Page 33: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/33.jpg)
Gallbladder
• The gallbladder stores and concentrates bile.
• Bile release into duodenum1. Fatty chyme stimulates release of CKK and
secretin.2. CKK enters bloodstream3. Bile salts and secretin in the blood stimulate
liver to rapidly produce bile.4. Vagal stimulation leads to weak
contractions.5. CKK causes gallbladder to contract and the
hepatopancreatic sphincter to relax; bile enters duodenum
![Page 34: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/34.jpg)
Pancreatic juice
• Insulin & Glucose Regulation
![Page 35: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/35.jpg)
![Page 36: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/36.jpg)
![Page 37: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/37.jpg)
Digestion in Small intestine: chemical
• Digestion of carbohydrates– Pancreatic amylase– Brush-border enzymes
• Digestion of proteins– Enzymes from pancreatic juice– Brush-border peptidases releases single AAs
• Digestion of lipids– Digestion & Absorption of Fats
• Digestion of nucleic acids
![Page 38: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/38.jpg)
![Page 39: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/39.jpg)
![Page 40: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/40.jpg)
![Page 41: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/41.jpg)
Digestion in Small intestine: mechanical
• Segmentation leads to chyme being moved backwards and forwards.
• Parasympathetic input increases intensity of contractions; sympathetic input decreases intensity.
• Peristalsis occurs after nutrients are absorbed; regulated by motilin.–Migrating motility complex
• Movement through ileocecal sphincter is enhanced by gastrin.
• Once meal has passed through sphincter back pressure keeps the valve closed
![Page 42: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/42.jpg)
![Page 43: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/43.jpg)
![Page 44: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/44.jpg)
Water
• Water moves in both directions and follows flow of electrolyhtes
![Page 45: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/45.jpg)
Large intestine (5 ft)
• Mechanical digestion—haustral churning, peristalsis, mass peristalsis
• Chemical digestion
• Absorption• Feces formation• Reflexes in the
Colon
![Page 46: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/46.jpg)
Ulcerative Colitis
![Page 47: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/47.jpg)
Defecation reflex
• Mass peristaltic movements
• Voluntary contractions of diaphragm and abdominals
• Parasympathetic input
• Voluntary input
![Page 48: The Digestive System. Organ groups of digestion Alimentary organs – Mouth – Pharynx – Esophagus – Stomach – Small and large intestine Accessory digestive.](https://reader030.fdocuments.us/reader030/viewer/2022012910/56649de35503460f94ada076/html5/thumbnails/48.jpg)
Resources
• Human Digestion• Heart Burn Video• Peristalsis Animation • Digestive System