Digestive Flashcards
what is digestion
- breakdown of ingested food
- absorption of nutrients into the blood
- concentration and removal of waste products
what is metabolism
- production of cellular energy (ATP)
- regulation of cellular activities
what are the 2 main functional groups of organs
- alimentary canal (continuous hollow tube)
- accessory digestive organs
structures of the alimentary canal
- mouth
- pharynx
- esophagus
- stomach
-small intestine - large intestine
anus
functions of the salivary glands
- Lubrication/binding
- Solubilization of dry food
- Oral hygiene – flushes away debris
- Begins starch digestion (salivary amylases)
- Alkaline buffering
-Evaporative cooling (ie, important in dogs)
function of incisors
rip and cut
function of canines
tear and pierce
function of premolars
grind and shear
function of molars
grind
different types of teeth
- incisors
- canines
-premolars
-molars
how many primary and secondary teeth
20 primary
32 secondary
first step from mouth to stomach
mastication (chewing food)
- teeth
second step from mouth to stomach
deglutition (swallowing)
- oral, pharyngeal, esophageal
mouth, pharynx and upper esophagus are muscles innervated by what neurons
somatic motor neurons
middle and lower esophagus are muscles innervated by what neurons
autonomic neurons
what does the esophagus connect
connects pharynx to the stomach
what is peristalsis
food moves by a wake-like muscular contraction
- pushes bolus into the stomach
how do muscle layers in the stomach help with digestion
the smooth muscle layers in the stomach run along the length of the organ, around the organ and also in an oblique direction. these muscles help mix and mechanically break up food in the stomach
gastric pits
are the openings of the gastric glands
what cells make up the gastric glands
- mucous cells
- chief cells
- parietal cells
what does mucous cells secrete
mucus
what does parietal cells secrete
HCl, intrinsic factor (B12)
what do chief cells (zymogenic) secrete
secrete pepsinogen
what causes peptic ulcers and how are they related to helicobacter pylori
- erosions of the mucosa in the stomach can lead to peptic ulcers where the stomach digests itself
- is caused by the bacteria helicobacter pylori, which infects the GI tract of about 50% of adults worldwide