Anatomy of the Digestive System Minimal Requirements for Lab
Identify Structure and Name Function
- Digestive (GI) tract (alimentary canal):
- Oral cavity
- Hard palate
- Palatine process (horizontal plate) of the maxillary bone
- Palatine bone
- Soft palate
- Uvula
- Tongue
- Papilla
- Filiform
- Fungiform
- Circumvallate
- Cranial nerve (C.N.) innervation
- Sensory – CN VII, IX, and X
- Motor – CN XII
- Lingual frenulum
- Tonsils
- Palatine
- Lingual
- Pharyngeal
- Pharynx
- Nasopharynx
- Oropharynx
- Laryngopharynx
- Layers of digestive tract
- Mucosa
- Simple columnar epithelium
- Lamina propria
- Muscularis mucosa
- Submucosa
- Submucosal plexus
- Submucosal glands
- Arteries and veins
- Muscularis externa
- Inner circular layer
- Myenteric plexus
- Outer longintudinal layer
- The outer most layer of digestive tract consists of either the:
- Adventitia − outside of a closed internal body cavity or
- Serosa − inside of a closed internal body cavity
- Esophagus
- Lower esophageal (gastroesophageal or cardio-esophageal) sphincter (LES)
- Stomach
- Cardiac region (cardia)
- Fundus
- Body
- Pyloric region
- Pyloric sphincter
- Lesser curvature
- Lesser omentum
- Greater curvature
- Greater omentum
- Rugae
- Gastric pits and glands
- Surface mucous (mucous neck) cells (note: these are not goblet cells)
- Parietal cells that secrete HCl (large cells, often stained red)
- Chief cells that produce pepsinogen (smaller cells, often stained blue)
- Enteroendocrine cells
- 3 layers of smooth muscle
- Oblique
- Inner circular
- Outer longitudinal
- Serosa
- Small intestines
- Mesentery proper
- Duodenum
- Jejunum
- Ileum
- Ileocecal valve and junction
- Large intestine
- Mesocolon
- Taenia coli – the outer longitudinal muscle has been reduced to 3 bands
- Haustra
- Colon
- Cecum
- Vermiform appendix
- Ascending colon
- Right colic (hepatic) flexure
- Transverse colon
- Left colic (splenic) flexure
- Descending colon
- Sigmoid colon
- Rectum
- Anus
- anal canal
- Anal orifice
- Internal anal sphincter (smooth muscle)
- External anal sphincter (skeletal muscle)
- Accessory structures
- Tooth: be able to identify the different types of teeth in the upper & lower jaw
- Incisors - central and lateral
- Cuspids (canine)
- Premolars (bicuspids) - 1st and 2nd
- Molars - 1st, 2nd, and 3rd (wisdom teeth)
- Each tooth will consist of the following:
- Crown (clinical and anatomical)
- Enamel
- Dentin
- Pulp cavity containing pulp (blood vessels and cranial nerves)
- Root
- Dentin
- Cementum
- Periodontal ligament
- Root canal containing blood vessels and nerves
- Gingiva (gum)
- Salivary glands
- Parotid glands and duct (100 % serous cells)
- Submandibular glands and duct (70% serous cells and 30% mucous cells)
- Sublingual glands and duct (30% serous cells and 70% mucous cells)
- Liver (gross structures):
- Lobes:
- Right
- Left
- Caudate
- Quadrate
- Portal triad containing:
- Hepatic portal vein
- Hepatic artery
- Hepatic bile ducts
- Hepatic vein
- Falciformligament
- Round ligament
- Hepatic ducts
- Right
- Left
- Common
- Gallbladder
- Cystic duct
- Common bile duct
- Hepatopancreatic ampulla and sphincter
- Liver (internal structures)
- Lobule
- Central vein
- Sinusoids
- Kupffer cell (liver macrophages)
- Hepatocytes
- Portal triad
- Bile duct
- Hepatic artery
- Hepatic portal vein
- Bile canaliculi
- Connective tissue septum
- Pancreas
- Accessory pancreatic duct
- Minor duodenal papilla
- Main pancreatic duct – joins with the common bile duct
- Hepatopancreaticampulla and sphincter
- Major duodenal papilla
- Connective tissues within the abdominopelvic cavity
- Mesentery proper – small intestine
- Mesocolon – large intestine
- Histology of the digestive tract
- Esophagus
- Stratified squamous epithelium
- Submucosal mucous glands
- Skeletal and/or smooth muscle
- Adventitia
- Gastroesophageal junction: epithelial tissue type abruptly changes
- Stomach (fundus)
- Smooth muscle layers
- Oblique (inner)
- Circular (middle)
- Longitudinal (outer)
- Gastric pits and gastric glands
- Small intestines
- 4 levels of folding to maximize efficiency
- Arranged like a sloppily coiled rope (macroscopic)
- Plicae circulares (plications)
- Villi
- Microvilli
- Goblet (mucous) cells
- Intestinal glands (crypts)
- Lacteal
- Blood capillaries
- Duodenum
- Brunner’s (submucosal) glands in the submucosal layer
- Duodenal papilla
- Jejunum
- Only connective tissues in the submucosal layer
- Ileum
- Peyer’s patches
- Large intestines
- Taenia coli – the outer longitudinal muscle has been reduced to 3 bands
- Haustra
- Histology of the accessory glands
- Parotid glands
- 100 % serous cells
- Salivary ducts
- Submandibular (submaxillary) glands
- 70 % serous cells and 30% mucus cells
- Salivary ducts
- Sublingual glands
- 70 % serous cells and 30% mucus cells
- Salivary ducts
- Liver
- Lobule
- Central vein
- Sinusoids
- Kupffer cell (liver macrophages)
- Hepatocytes
- Portal triad
- Bile duct
- Hepatic artery
- Hepatic portal vein
- Bile canaliculi
- Connective tissue septum
- Pancreas
- Acinar cells (exocrine cells)
- Pancreatic islets (endocrine cells)
- Duodenum
- Brunner’s (duodenal or submucosal) glands in the submucosa
- Jejunum − note the presence of pronounced plications and villi
- Submucosa contains connective tissues, but nothing extra
- Ileum
- Peyer’s patches (lymphatic nodules) in the submucosa
- Colon: note abundance of goblet (mucous) cells
- Haustra – created by the outer longitudinal muscle layer being reduced to bands (taenia coli)
- Cat dissection:
- Esophagus
- Gastroesophageal junction
- Stomach
- Rugae
- Greater omentum
- Lesser omentum
- Pyloric sphincter
- Liver (note difference between humans and cats)
- Gall bladder
- Small intestine
- Duodenum
- Jejunum
- Ileum
i. Ileocecal valve
- Large intestine
- Cecum
- Ascending colon
- Transverse colon
- Descending colon
- Hepatic and splenic flexures
- Mesentery proper
- Mesocolon
- Rectum
- Anus
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