unit 3 digestive system Flashcards
digestion
hydrolysis of large molecules into monomers within the gastrointestinal tract
absorption
transportation of monomers across the wall of the small intestine in the blood lymph
alimentary canal (GI) tract
mouth to anus
accessory digestive organs
digestive glands
what is the digestive process?
- ingestion
- propulsion
- swallowing and peristalsis - mechanical breakdown
- segmentation - digestion
- absorption
- defecation
what are the 4 layers of the gastrointestinal tract
- mucosa
- submucosa
- muscular externia
- serosa
what are the three sublayers of the mucosa?
- epithelium
- lamina propria
- muscular mucosae
submucosa characteristics
- connective tissue
- blood and lymph vessels
- lacteals
muscular externa characteristics
- inner circular muscle
- outer longitudinal layers
- spinchers
- smooth muscle
peritoneum
serous membranes of abdominal cavity
mesentery
double layer of peritoneum, layers are fused back to back
intraperitoneal organs
in cavity
retroperitoneal organs
outside or posterior to cavity
oral cavity characteristics
-oral orifice; opening of mouth
stratified squamous epithelium.
tongue
interacting bundles of skeletal muscle
functions of tongue
- gripping, repositioning, mixing of food
- formation of bolus, food and saliva
- initiate swallowing, speech and taste
what are the 4 different tongue papillae
- filiform papillae- rough, keratinized
- fungiform papillae- color
- valiate papillae- the V
- foliate papillae- ridges on side
functions of saliva
- cleanses mouth
- dissolve food for taste
- moisten food, bolus
- breakdown of starch with amylase
what are the three parts of the esophagus?
- esophageal hiatus- passes diaphragm
- cardial orifice- joins stomach
- gastroesophageal sphincter