Hormones of GI Tract (Quiz) Flashcards
which type of glands release their contents onto an epithelial surface directly or via a duct
- exocrine
which glands have lost contact with the epithelial cell surface completely and release secretions into the blood stream
- endocrine
what is the largest endocrine organ in the body based on surface area
- GI tract
regulation of GI secretions through three mechanisms
- direct stimulation when food enters GI tract
- autonomic stimulation from sympathetic or parasympathetic system
- influence of hormones in the blood
exocrine secretions of the salivary glands
- salivary amylase
- lingual lipase
the three glands that produce saliva
- sublingual
- submandibular
- parotid
saliva production controlled by ______ nervous system
- autonomic (both sympathetic and parasympathetic)
parotid glands secrete more ______ saliva and the sublingual glands secrete more ________ saliva
- parotid - serous
- sublingual - mucinous
components of saliva
- mucous
- lysozyme
- lactoferrin
- secretory IgA
- amylase
- lingual lipase
function of mucous
- lubricates oral cavity and food
- buffer for acid in stomach
- forms protective film on teeth
function of lysozyme
- attacks bacterial cell walls
function of lactoferrin
- chelates iron and prevents growth of organisms that use iron for growth
function of secretory IgA
- immune active against bacteria and viruses
function of salivary amylase
- initial breakdown of starch in mouth and first part of stomach
how can salivary amylase survive a bit in the stomach
- saliva provides some buffer with bicarb
function of lingual lipase
- fat digestion
function of parietal cells
- secrete acid and intrinsic factor
function of intrinsic factor
- required for vitamin B12 absorption
where are parietal cells located
- in body and fundus of stomach
location of enterochromaffin-like cells
- middle of gastric pits
function of enterochromaffin-like cells
- histamine secretion which leads to acid stimulation
location of chief cells
- deep in gastric pits
function of chief cells
- secrete pepsinogen which is converted to pepsin and starts protein breakdown