Download Gastrointestinal Tract

Anatomy of Gastrointestinal Tract
Gastrointestinal Tract
1. hollow, continuous,
muscular tube
2. food inside is
technically outside of
the body because it
open at both ends.
Yum
!
Mouth
1. Includes teeth, tongue &
salivary glands
2. Begins digestion process
through :
a. mechanical movement
(chewing/mastication)
b. chemical process (mixing saliva)
Enzymes
(Chemical processing)
• 3 categories
• Carbohydrases (breaks down carbs)
• Proteases (breaks down protein)
• Lipases (breaks down fats / lipids)
Chewing = “Mastication”
Teeth – mechanically break down food into smaller
pieces
Tongue – manipulate food to the back of the mouth
towards pharynx
Fun facts!
Tonsils – what are they for?
• “Test the air/food coming in for bacteria and
viruses” – thought to help the body build up antibodies against them
• Scientists see no need for them typically after age
3
**can become infected themselves, to the point of
needing removal
Fun facts!
Uvula – what is it?
• “hangy-thing” in the back of your throat
• serves to rise up when swallowing to help prevent
food from entering into the nose
**Like the tonsils, can also become infected to the
point of needing removal
Salivary glands
Three glands:
• ___________________- most superior and
posterior
• _____________________– most anterior
• (sub = under lingual = tongue)
• ____________________– most inferior
• (sub = under mandible = jaw)
Salivary glands
Purpose:
• Secrete __________________________________to
chemically break down food
Converts:
polysaccharides  maltose
(complex  simpler)
Background Information
Carbohydrates
Most complex  Simplest
Polysaccharides  Disaccharides  Monosaccharide
(starches)
(maltose)
(glucose)
Salivary Amylase
Summary…partial breakdown of carbs
Converts:
polysaccharides 
disaccharides
(starch)
(sugar)
Swallowing = “Deglutition”
3 steps
1) ____________phase “voluntary chewing”
2) ___________________phase “swallowing reflex”
- medulla oblongata = swallowing center
3) __________________phase “traveling
involuntarily down
esophagus”
Peristalsis
• Involuntary muscle contractions to move digestive
food from point A to point B
• Esophagus
• Small Intestine
• Large Intestine
peristalsis in action