Digestion Anatomy Flashcards
Voluntary processes
Swallowing
Involuntary processes
Peristalsis
Digestion mechanical or chemical?
Both
Food that is physically prepared for chemical digestion
Mechanical digestion
Examples of mechanical digestion
Chewing, mixing of food with saliva using tongue and cheek muscles
Rhythmic constrictions of intestine (which mixes food w digestive juices)
Segmentation
When does absorption occur?
When nutrients vitamins minerals and water are moved from the lumen of intestinal tract into blood or lymph
Mechanical processing, moistening, mixing w saliva
Oral cavity, teeth, tongue
Transport or minerals to stomach
Esophagus
Secretion of bile, storage of nutrients,
Liver
Storage and concentration of bile
Gallbladder
Dehydration and compaction of indigestible materials in preparation for elimination
Large intestine
Secretion of lubricating fluid containing enzymes that break down carbohydrates
Salivary glands
Muscular propulsion of materials via acid and enzymes, mechanical processing through muscular contractions
Stomach
Exocrine cells secrete buffers and digestive enzymes, endocrine cells secrete hormones
Pancreas
Enzymatic digestion and absorption of water, organic substrates, vitamins and ions
Small intestine
Moist epithelium that lines alimentary canal lumen from mouth to anus
Ranges in function (protection, absorption, secretion)
Mucosa
Loose areole ct supporting mucosa
Laminate propia
Thin double layer that alters shape of lumen with contractions
Muscularis mucosa
Highly vascularized areolar ct that connects mucosa to third layer
Submucosa
Controls secretion of glands
Sub mucosal plexus
Functions in peristalsis and segmentation, formation of sphincters (controls 1 way movements)
Muscularis externa
Autonomic nerve plexus that helps control the gut movements via peristalsis and segmentation
Auerbach’s or myenteric plexus
Cells that secrete HCl and intrinsic factor, are acidophilic
Parietal cells
Cells that secrete pepsin and gastric lipase
Chief cells
Cells that secrete alkaline mucus that contains bicarbonate
Goblet cells
Cells that secret a thin mucus that is chemically different than the mucus produced by goblet cells
Mucus neck cells
Helps absorb vitamin B12 thus necessary for RBC production
Intrinsic factor
Peptide hormone that stimulates! secretion of gastric acid (HCl)
Gastrin
