Gastro anatomy 1 Flashcards
What are the general functions of the gastrointestinal system
motility - mix the luminal content + exreate waste
secreations - glands, mucus, hormones, serous fluid
absorbtion - nutriance from lumin -> internal
digestion - breaking nutriance down to components
What are the main+ acessory structures of the GI system
main structures - esophogous -> stomach -> small intestine -> large intestine (
- each which has a unique envrionment for function
acessory structures: teeth -> salivatory galnds -> liver, pancrease, gallblader
sphincters: block off ends -> seperate environments
what is the epithelium of the GI systems
mouth, oro/larngo pharnx, esophogous, anus -> strattified squamous epithelium
- good to prevent abrasions + protection
stomach, small intestine, large intestine -> simple comumnar epithelium
- good for secreation + absorbtion
What are the four standard layers of the GI tube
muscosa: epithelium, bament membrane, laima propria, muscularise mucosae (
- sometimes contains glands
submucusa: FCT, blood vessles, lymphatics, glands, nerves
- secreation controled by - sub mucosal plexus = part of enteric nervous sytem
muscularis: smooth muscle layers
inner = circular, outer = longitudinal
adventita: FCT
+ serosa when in peritoneal cavity
What type of glands do we find in the GI tract (general types not specific)
+ gland section names
unicellular glands - 1 gland present
multicellular glands:
simple - 1 duct
complex - multiple ducts (salitory glands)
cell cluster = acinus
duct secreates bicarbonate (pH buffer)
What are the properties of the unicellular goblet cells
Secreate mucus -> lubvrication + protection
secreated from apical mucus granuals
basal nucleus
What is the function of the mouth/ oral cavity
start digestion: mechanical + chemical (amylase)
- utilises lubrication to minimise damage from glands
pathway: faucets -> oropharnx -> larngopharynx -> esophagous
What are the glands of the mouth and oral caivtiy
salivatory glands - come in pairs
parotid gland: serous fluid + amylase, posterior oral cavity
subligual: mucus, anterior below toung
submandibular:mixed, posterior below tounge
acinar cell secrete: enzymes, serous fluid
What are the general properties of the esophagus
posterior to the trachea : run pharynx -> stomach
uvula + soft palate prevent bolus to nasopharynx : epiglotis prevents bolus to epiglottis
strattified sqamous epithelium -> mucus glands seccreate via ducts to surface, no goblet cells as not columar epithlium
glands in submucosa -> when close to stomach also in mucosa
muscularis moves bolus to stomach
top: 1/3 skeletal, 1/3 mixed, 1/3 smooth: bottom - muscle type
highly folded mucosa + submucosa = enables expantion for bolus
