Teeth, pharynx and esophagus, stomach, digestive system

mastication

chewing food into smaller pieces

how many teeth are dentition (baby teeth)

20 during 6 and 24 months of age

how many adult permanenet teeth do you develope

32

all molars except the 3rd one is

wisdom teeth

teeth classification:

incisors?

canines?

premolars?

molars?

incisors: cutting

canines: tear or puncture

premolars: grinding or crushing food

molars: best grinders

canine tooth interior anatonmy:

crown?

root?

dentin?

pulp?

crown: hardest enamel

root: bone in your jaw connected to the crown

dentin: under enamel

pulp: nerves, blood vessel, connective tissure

what is an impacted tooth?

treatment?

tooth remained trapped in the jawbone

treament: surgical removal

Dental caries (cavities)

Dental plaque

prevention?

dental cavities: demineralization of enamel and dentin from bacterical action

Dental plaque: sugar, bacteria, and dedbris adheres to teeth

prevention: daily flossing and brushing

Gingivitis

plaque calcifies to form calculus (tartar)

Perioddontitis (periodontal disease)

neglected gingivitis can escalate to disease

• immunce cells attack not only baterical intruders but your body tissues in tooth.

The pharynx

type of epithelium?

food passes from mouth into oropharynx and then into laryngopharynx.

• allows passage food, fluids, and air

• stratified dsquamous epithelium

esophagus has 4 what?

esophageal muscosa contains what epithelium? it changes to what epithelium at stomach

4 alimentary canal layers

stratified squamuos epithelium then to simple columnar at stomach

esophagus:

pierces diaphragm at?

joins stomach at?

what surrounds cardial orifice?

pierces diaphragm at: esophageal hiatus

joins stomach at: cardinal orifice

what surrounds cardial orifice: gastroesophageal (cardiac) sphincter

clinical:

Heartburn

causes?

first symptom?

can also be caused by?

heartburn: caused by stomach acid regurgitating into esophagus

first symptom: gastroesophageal reflux disease (GERD)

also caused by: hiatal hernia

the stomach:

what is the name of converting bolus of food to paste?

when the stomach is empty it forms folds called?

a termporary storage tank that starts chemical breakdown of protein digestion.

converts bolus of food to paste like chyme

when empty, stomach mucosa forms many folds called rugae

what nervous system supplies stomach?

parasympathetic fibers are supplied by?

autonomic nervous system

supplied by vagus nerve

muscularis externa are smooth muscles that allow stomach to?

churn, mix, move, and pummel chyme. then rams it into small intestine

the stomach’s modified mucosa:

consist of what epithelium?

secretes two layer coat of?

simple columnar epithelium

two layer coat of: alkaline mucus

gastric glands produce what?

gastric juice

the stomach’s secretory glands:

4 types of gland cells that produce gastric juice

muscous neck cells

parietal cells

chief cells

enteronendocrine cells

cells of gastric glands:

parietal cells secretion?

chief cells secretion?

parietal cells secretion: hydrochloric acid (HCL)

chief cells secretion: pepsin

cells of gastric glands:

enteroendocrine cells secretion?

serotonin?

histamine?

hormones:

somatostain?

gastrin?

serotonin: stimulates muscle cell contractions

histamine: stimulates parietal cells to releaces HCI

hormones:

somatostatin: inihibts all gastric gland secretions

Gastrin: stimulates HCI secretion

the stomach’s protective mucosal barrier:

3 factors of stomachs muscosal barrier protection?

1. bicarbonate-rich mucus

2. tight junctions - prevent juice seeping underneath tissue

3. damaged epithelial cells are quickly replaced

clinical:

gastritis

peptic or gastric ulcers?

most ulcers caused by bacterum __?

inflmmation caused by a breach in stomach’s mucosal barrier

peptic or gastric ulcers: causes erosions in stomach wall

ulcers caused mostly by helicobacter pylori

digestive processes in stomach:

milk protein (casein) broken down by ___ in infanats?

stomach function secretion of ____ for vitamin b12 absoprtion

rennin

intrinsic factor

regulation of gastric secretion:

neural mechanism:

vagus nerve stimulates?

sympathetic stimulaties?

hormonal mechanisms:

gastrin stimulates?

vagus nerve stimulates: increase secretion

sympathetic stimulaties: decreases secretion

gastrin: stimulates HCI secretion