Digestive System

Alimentary Organs

mouth

pharynx

esophagus

stomach

small intestine

large intestine

Acessory organs

teeth

tongue

salivary glands

liver

gallbladder

pancreas

difference of alimentary canal and the accessory organs

food goes into the alimentary canal but does not enter the accessory organs and just assists.

mechanical digestion

physcially breaking down the food

chemical digestion

food broken down chemically

3 cells that make up the gastric glands and what it secretes

mucous cells- mucous

parietal cells-intrinsic factor

chief cells-pepsinogen

the cells in the gastric glands make up what combined?

gastric juice

what is gastrin

a hormone that stimulates the release of gastric juice which leads to peristalsis

What is chyme

food mixed up in the stomach to form a semifluid paste

mouth functions

breaks down, moistens and receives food.

teeth functions

breaks off food, and the mastication of food (chew)

Tongue functions

mixes saliva with food

moves bolus to the pharynx

has papillae (which help grip food)

Hard palate is?

roof of mouth

Soft palate and uvula?

uvula is attached to the soft palate

both move up and back when swallowing to paritally block nasal cavity

Tonsil, function, amount and contents

3 sets

all contain lymphatic tissue

has WBC to fight infections

types of tonsils

palatine tonsils

pharyngeal tonsils (adenoids)

lingual tonsils

Salivary Glands function

release saliva thru small ducts to bind and moisten foods

contents of saliva

water

mucous

Salivary amylase (enzyme that starts chem digestion of carbohydrates)

lysozyme (antibacterial enzyme to protect teeth)

Pharynx functions

transports food to esophagus

(no digestion/absorption)

Esophagus function

transports food to stomach

esophagus charcteristics

muscluar tube

passes thru opening in diaphragm to the stomach (esophageal hiatus)

Hiatal hernia

when part of stomach breach esophageal hiatus

heart burn

when stomach acid enter esophagus

Gastro esophageal reflux disease (GERD)

lower esophageal spchinter aka

cardiac sphincter

how many sphincters in system

6

Upper esophageal sphincter

Lower esophageal sphincter

Pyloric sphincter

hepatopancreatic sphincter

Ileocecal sphincter

Internal anal sphincter

sphincter is what

ring of smooth and skeletal muscle and relax to allow passage and contrict to block

regions of the stomach

fundic region

cardiac region

body region

pyloric region

stomach characteristics

4 regions

pouch like

holds 1.5L

3 layers of smooth muscle fibers for xtra churning action

3 sm fibers of stomach

oblique

longitudal

circular

Stomach-

Gastric pits?

indentations on inner stomach wall

Stomach-

Gastric Glands location

deep within the gastic pits

Gastric glands- paretial cells

intrinsic factor, helps body absorb vit b12 and needed for hematopoesis

Stomach absorbtion

very little with the exception of h20 and medicine

3 segments of the small intestine

duodenum, jejunum illeum,

what segment of the small intestine has the most enzyme activity and nutrient absorption

duodenum

4 layers of the alimentary canal (superficial to deep)

Serosa

muscularis

sub mucosa

mucosa

peristalsis?

rythmic contraction of smooth muscle to move food along

bolus

a rounded mass of food, mucous and saliva formed by the tounge and teeth

2 structures that make sure food goes in the right direction when swallowed

epiglottis

uvula

Chyme goes into the duodenum through the

pyloric sphincter

what does secretin do

neutralizes the acidity of chyme when entering the duodenum

stimulates the pancreas to release pancreatic juice into the duodenum

chloecytokenin(CCK)

hormone from the small intestine

stimulates the release of bile from the gallbladder

bile and pancreatic juice must pass what to reach the small intestine

hepatopancretic sphincter

Liver is the…

largest visceral organ

liver functions (5)

stores glucose

stores vitamins

metabolizes protiens, fats and cholesterol

detoxification

formation and secretion of bile into gallbladder

gallbladder characteristics

small thin sack used for storing concentrated bile and cholesterol-based solution

gallbladder functions (4)

used for emulcification of fats

increased SA

allows enzymes to work efficently

absorbes bile fluids and increases concentration

what is a gallstone

when too much water is absrobed in the gallbladder and cholesterol turns into a solid form

small instestine charactersitics

6m-20ft

extends from pyloric to ileocecal sphincter (end of stomach to start of large intestine)

3 segments

the small intenstine secretes…

intestinal enzyme to finish the breakdown of food

chemical digestion in small intesting

1. intestinal lipase-digestion of fatty acids

2. amino peptidase- splits amino acid

3. sucrase, maltase, lactase- act upon diaccharides (carbs sugars)

4. nucleases- act upon nucleic acid

Small intestine

has irregular mucosal surface called….

with fingerlike porjections called…

plicae circularis

villi

small intestine

both plicae circularis and villi do what

increase surface area

small intestine

villi function

has capillaries for absrobtion of glucose and amino acids

has lactels for absorption of fatty acids

infection of small intestine leads to

increase of peristalsis and move material faster through intestines

peristaltic rush- diarrehea

ileocecal valve (sphincter)

regulates movement of material into the large intestine

first segment of the large intestine (colon)

cecum

has vermiform appendix attatched

segments of the large intestine

cecum

acdending colon

transverse colon

descending colon

sigmoid colon

rectum

anal canal

anal canal sphinceters

internal anal sphincters- s.m involuntary and contracted until pressure from feces

external anal sphincter- skel. muscle, voluntary, can be contracted to hold in waste)

defaction and elmination

waste exiting body

enterokinase

Enterokinase converts trypsinogen into trypsin, triggering pancreatic protein digestion.

secreted from small intestine