last exam

responsible for ingestion , mastication and deglutition

produce a fluid in the mouth that helps cleanse the mouth and teeth and that lubricates, dissolves , and begins the chemical breakdown

forces the food to the back of the mouth for swallowing , places food in contact with the teeth

forms a semisolid waste material through haustral churning and peristalsis

passageway for food , fluid , and air , involved in deglutition

composed of enamel , dentin , and pulp cavity , used in mastication

contain acini that release juices containing several digestive enzymes for protein , carbohydrate , lipid , and nucleic acid digestion and sodium bicarbonate to buffer stomach acid

storage area for bile

responsible for churning , peristalsis , storage and chemical digestion with the enzyme

contains aggregated lymphatic follicles ( Peyer's patches ) in the mucosa

produced and secretes bile

contains duodenal ( Brunner's ) glands in the submucosa

coiled tube attached to the cecum

collapsed , muscular tube involved in deglutition and peristalsis

an enzyme that initiates carbohydrate digestion in the mouth

the principal triglyceride-digesting enzyme in adults

stimulates secretion of gastric juices and promotes gastric emptying

secreted by chief cells in the stomach , a proteolytic enzyme

a nonenzymatic fat-emulsifying agent

causes contraction of the gallbadder and stimulates the production of pancreatic juice rich in digestive enzymes

secreted by glands in the tongue, begins breakdown of triglycerides in the stomach

microvilli of the small intestine that increase surface area for absorption , also contain some digestive enzymes

fingerlike projections of the mucosa of the small intestin that increase surface area for digestion and absorption

produce hydrochloric acid and intrinsic factor in the stomach

stomach enteroendocrine cells that secrete gastrin

longitudianl muscular bands in the large intestine , tonic contractions produce haustra

lymphatic capillary used for chylomicron absorption in the small intestine

groups of lymphatic nodules in the small intestine

controls the GI tract motility and secretions of GI tract organs

large mucosal folds in the stomach

secrete pepsinogen and gastric lipase in the stomach

the removal of electrons for m an atom or molecule resulting in a decrease in potential energy

• - attachments to stomach and duodenum
• - drapes downward over coils of small intestine
• - then turns upward and attaches to transverse colon
• - contains a considerable amount of adipose tissue

attaches liver to anterior abdominal wall and diaphram

suspends stomach and duodenum from liver

binds jejunum and ileum to posterior abdominal wall

binds transverse colon and sigmoid colon to posterior abdominla wall

• - oral or buccal cavity
• - formed by cheeks , hard and soft palates , and tongue
• - palate separates oral cavity from nasal cavity
• - makes it possible to chew and breathe at the same time

• - ordinarily just enough is secreted to keep mouth and pharynx moist and clean
• - when food enter mouth , secretion increases to lubricate , dissolve and begin chemical digestion

• - parotid
• - submandibular
• - sublingual

• - mostly water
• - provides a medium for dissolving food
• - solutes include : ions , dissovled gases , urea , uric acid , mucus, immunogloblulin A , lysozyme , and salivary amylase acts of starch
• - not all salivary glands produce the same saliva

• - controlled by autonomic nervous system
• - parasympathetic stimulation promotes continuous secretion of moderate amoutn of saliva
• - chemical in food stimulates heavy secretion of saliva sympathetic decreases salivation

• - accessory digestive organ
• - skeletal muscle covered by mucous membrane
• - maneuvers food for chewing , shapes food into a rounded mass , forces food back for swallowing
• - lingual glands secrete lingula lipase: act on triglycerides

• - accessory digestive organ
• - periodontal ligament anchors teeth to walls of alveolar sockets
• - three major regions: crown , root , and neck
• - dentin forms majority of tooth: calcified connective tissue , dentin of crown covered by enamel , root covered by cementum
• - pulp cavity enclosed by dentin: contains pulp ( blood vessels , nerves , and lymphatic vessels )
• - incisors , cuspids ( canines ) premolars , molars

• - deciduous 20 teeth
• - permanent 32 teeth

• - chewing or mastication
• - food manipulated by tongue , ground by teeth , and mixed with saliva
• - foms bolus
• - soft , flexible , easily swallowed mass

• - salivary amylase secrected by salivary glands acts on starches ( polysaccharides )
• - only monosaccharides can be absorbed into bloodstream
• - continues to act until inactivated by stomach acid
• - lingual lipase secreted by lingual glands of tongue acts on triglycerides
• - becomes activated in acidic environment of stomach

• - food passes from mouth into pharynx
• - 3 parts: nasopharynx , oropharynx , laryngopharynx
• - muscular contractions of pharynx propel food into esophagus

functions only in respiration

digestive and respiratory functions

digestive and respiratory functions

• - collapsible muscular tube , passes through esophageal hiatus ( opening in diaphragm )
• - secretes mucous and transports food
• - no enzymes produced no absorption
• - layers : mucosa - protection against wear and tear

• 1. upper esophageal sphincter ( UES ) : regulates movement from pharynx into esophagus
• 2. lower esophageal sphincter (LES ) : regulates movement from esophagus into stomach acid reflux

adventitia: attaches to surrounding structures

• - serves as mixing chamber and holding reservoir
• - mixes saliva , food , and gastric juice to form chyme
• - forces a small quantity of chyme into intestine at appropriate interval
• - MOST distensible part of GI tract
• - in stomach : digestion of starch continues , digestion of proteins and triglycerides begins , the semisolid bolus os converted to a liquid
• - certain substances are absorbed

• 1. cardia
• 2. fundus
• 3. body
• 4. pylorus

large folds of mucosa in the stomach

• mucosa- gastric glands open into gastric pits
• - three types of exocrine gland cells produce gastric juice
• . mucous neck cells- secrete mucus
• . parietal cells- secrete intrinsic factor and HCL
• . chief cells- endocrine cell secrete gastrin
• submucosa
• muscularis - additional inner oblique muscle layer
• serosa - part of visceral peritoneum

• - mixing waves
• - gentle , rippling peristaltic movements
• - macerate food and mix it with gastric juice creating chyme

• - food may remain in fundus for about an hour without mixing with gastric juice
• - digestion by salivary amylase continues until inactivated by acidic gastric juice
• - acidic gastric juice activates lingual lipase
• - digest triglycerides into fatty acids and diglycerides

• H+ and CL- separately but net effect is HCL
• - HCL secretion is stimulated by: parasympathetic nervous system , gastrin secreted by G cells
• - trigged by histamine
• -

• - kills many microbes
• - denatures proteins
• - stimulates secretions of hormones that promote flow of bile and pancreatic juice

absorption of vitamin B12

1. pepsinogen : is converted to pepsin when it comes in contact with HCL acid or active pepsin molecules , pepsin digests proteins

2. gastric lipase: splits triglycerides into fatty acids and monoglycerides

protect stomach epithelial cells from gastric juices , only allows for a small amount of nutrient absorption , some water , ions , short chain fatty acids , certain drugs ( aspirin ) and alcohol

• - Gastrin
• - stimulates parietal cells to secrete HCL
• - stimulates chief cells to secrete pepsinogen
• - contracts lower esophageal shincter
• - increases motility of the stomach
• - relaxes pyloric sphincter

• - lies posterior to greater curvature of stomach
• - connected to duodenum of small intestine by two ducts

1. pancreatic duct : joins common bile duct and becomes the hepatopancreatic ampulla , ampulla opens into duodenum at the major duodenal papilla

2. accessory duct : empties into duodenum superior to hepatopancreatic ampulla

- small clusters of glandular epithelial cells

• - exocrine portion of pancreas
• - secretes pancreatic juice

• - form endocrine portion of pancreas
• - secrete hormones glucogon , insulin , somatostatin and pancreatic polypeptide

• - water
• - some salts
• - sodium bicarbonate: buffers acidic gastric juice in chyme , stops action of pepsin
• - enzymes : pancreatic amylase digest starch
• - trypsinogen : converted to trypsin when reaches lumen of small intestine , trypsin inhibitor secreted by acinar cells to combine with any trypsin formed accidentally in pancreas of pancreatic juice / digest protein
• - pancreatic lipase : the principal triglyceride-digesting enzyme
• - ribonuclease and deoxyribonuclease : digest nucleic acids