#20 Upper Digestive System Flashcards
gastrointestinal tract in order
Mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus
gastrointestinal tract in order
Mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus
accessory organs in order
Teeth, tongue, salivary glands, pancreas, liver, gallbladder
digestive processes
propulsion, mechanical digestion, chemical digestion, absorption, defaction
propulsion
Swallowing (oropharynx)
Peristalsis (moving food) (esophagus, stomach, small intestine, large intestine)
mechanical digestion
Chewing (mouth)
Churning (stomach)
Segmentation (small intestine)
accessory organs in order
Teeth, tongue, salivary glands, pancreas, liver, gallbladder
defaction
removal of waste, things not broken down
propulsion
Swallowing (oropharynx)
Peristalsis (moving food) (esophagus, stomach, small intestine, large intestine)
mechanical digestion
Chewing (mouth)
Churning (stomach)
Segmentation (small intestine)
chemical digestion
Use of enzymes
In oral cavity, stomach, and small intestine
absoprtion
Nutrients and water to blood vessels and lymph vessels (small intestine)
Water to blood vessels (large intestine)
defaction
removal of waste, things not broken down
layers of gastrointestinal wall
lumen, mucosa, submucosa, muscularis, serosa (adventitia)
lumen
The space in the gastrointestinal tract (surrounded by mucosa)
mucosa
Epithelial lining closest to lumen, performs secretion and absorption, stratified squamous (esophagus) or Simple columnar (stomach and intestines
submucosa
Vascularized and innervated connective tissue
muscularis
Inner circular and outer longitudinal layers of smooth muscle (deep to submucosa)
serosa (adventitia)
Visceral peritoneum
Outside of peritoneal cavity = adventitia
Within peritoneal = serosa
Made of connective tissue (collagen and elastic fibers)
oral cavity
Lips and oral cavity are lined with non-keratinized stratified squamous epithelium
First site of mechanical and chemical digestion
hard palate
Bones of maxilla and palatine bones
Lined by mucosal membrane
soft palate and uvula are made of…
Made of mucosal membrane and muscle
tongue
Helps with mechanical digestion
Root body apex
papillae
Lingual frenulum
root
place of attachment
body
makes up bulk of tongue
apex
tip of tongue
submandibular gland
60-70% of saliva production
Just below mandible
parotid gland
25-30% of saliva production
Anterior to external ear (auricle of ear)
sublingual gland
3-5% of saliva production
Just underneath tongue
primary or deciduous teeth
20 total
8 incisors
4 canines
8 molars
permanent teeth
32 total 8 incisors (tear and cut food)
4 canines (piercing)
8 premolars (bicuspids) (grinding)
12 molars (grinding)
Nasopharynx
Lined with pseudostratified ciliated columnar epithelium
oropharynx and laryngopharynx
Lined with stratified squamous epithelium
deglutition (swallowing) phases
Voluntary phase
Bolus of food is pushed by tongue against the hard palate and moves toward oropharynx
Pharyngeal phase (involuntary)
Soft palate and uvula close off the nasopharynx
Larynx and hyoid elevate and the epiglottis closes over the laryngeal opening
Esophageal phase
(involuntary)
Peristaltic contractions of the esophageal muscle push the bolus toward the stomach
muscular tube of esophagus
upper and lower parts made up of?
Upper part: skeletal muscle
Lower part: smooth muscle
Esophagus
muscular tube, propels swallowed food to stomach through peristalsis
lined with stratified squamous epithelium, sphincter muscles
esophageal hiatus
sphincter muscles
Superior esophageal sphincter
Inferior esophageal sphincter (cardiac sphincter)
esophageal hiatus
Opening in the diaphragm
stomach
within abdominal cavity
Inferior to diaphragm
3 layers of muscle
functions of stomach
Storage of food (usually about 4 hours)
Mechanical digestion: churn food with gastric juice
Chemical digestion: initiate protein digestion
Limited absorption
surface epithelial cell
secretes mucus to protect the stomach wall (make up gastric pit in mucosa layer)
parietal cell
secretes hydrochloric acid and intrinsic factor
chief cell
secretes pepsinogen (enzyme that breaks down proteins)
make up gastric gland
Enteroendocrine cell:
secretes gastrin into the bloodstream
Gastric gland
made up of many different cells
Parietal cells that produce hydrochloric acid and intrinsic factor that travels with food to small intestine and helps in absorption of vitamin B12
reflux esphagitis
Acidic contents regurgitate into the esophagus
Chronic condition is called gastroesophageal reflux disease (GERD)
peptic ulcers
Erosion of stomach or duodenal mucosa
Majority of cases are associated with the bacterium Helicobacter pylori
Perforating ulcer
Eroded through entire wall
Treatments include:
Eliminating bacteria (antibiotics)
Eliminating acid
