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• What is the primary function of the digestive tract?

  Transporting and absorbing nutrients
• How do accessory digestive organs assist the digestive tract?

  They provide enzymes and lubricants
• What are the four layers of the GI tract?

  Mucosa, submucosa, muscularis externa, serosa/adventitia

  
• What role does the mucosa play in the digestive system?

  Forms a protective barrier and secretes substances
• How do specialized cells in the stomach epithelium contribute to digestion?

  They produce mucus and gastric acid
• What type of epithelium lines the esophagus?

  Stratified squamous moist epithelium

  
• What is the composition of the muscularis externa in the esophagus?

  Skeletal muscle transitioning to smooth muscle

  
• What characterizes the stomach's mucosa?

  Thick mucosa lined by surface sheet gland
• How does the muscularis externa of the stomach differ from other organs?

  It has three subdivisions instead of two

  
• What are the prominent features of the small intestine?

  Villi and intestinal glands

  
• What distinguishes the duodenum from the rest of the small intestine?

  Presence of glands in the submucosa
• What is the main characteristic of the large intestine's mucosa?

  Lacks villi and has straight intestinal glands
• What are the taeniae coli in the large intestine?

  Three longitudinal strips of muscle
• What is the innermost layer of the alimentary tract?

  Mucosa
• What does the submucosa contain?

  Blood and lymphatic vessels, nerves
• What is the outermost layer of the alimentary canal?

  Serosa/Adventitia
• What is the primary function of the rumen in ruminants?

  Storage and microbial fermentation of ingesta
• What type of epithelium lines the rumen?

  Keratinizing stratified squamous epithelium

  
• What is the function of the reticulum in ruminants?

  Further mechanical dissociation of digesta
• What characterizes the mucosal surface of the omasum?

  Large, thin, leaf-like structures called laminae
• How does the abomasum compare to the stomach of carnivores?

  Functionally and microscopically identical

  
• What distinguishes the equine stomach's mucosal regions?

  Proximal nonglandular and aboral glandular regions
• What is the function of the proventriculus in avian species?

  Glandular stomach producing pepsinogen and acid
• What is koilin in the gizzard?

  A protective carbohydrate-protein complex
• How does the liver process nutrient-rich blood?

  Through its intricate histological arrangement
• What is the structure of liver lobules?

  Hexagonal with portal areas/canals

  
• What do hepatocytes do in the liver?

  Filter and process nutrient-rich blood
• What is the role of Kupffer cells in the liver?

  Degrade worn out cellular structures
• How does bile travel in the liver?

  From hepatocytes to bile canaliculi
• What is the gallbladder's primary function?

  Store and concentrate bile
• What type of epithelium lines the gallbladder?

  Simple columnar epithelium
• What are the specialized capillaries in the liver called?

  Sinusoids
• What is the function of the perisinusoidal space of Disse?

  It separates hepatocytes from sinusoids
• What do stellate macrophages (Kupffer cells) do in the liver?

  They degrade worn out cellular structures
• Where do the sinusoids in the liver drain into?

  Central vein of the lobule
• What is the pathway of bile produced by hepatocytes?

  Released into bile canaliculi
• How does blood and bile travel in the liver lobule?

  Blood travels centrally, bile peripherally
• What is the primary function of the gallbladder?

  Stores and concentrates bile
• What type of tissue lines the mucosa of the gallbladder?

  Simple columnar cells
• What aids in the ejection of bile from the gallbladder?

  Smooth muscle fibers