DigestionBy: Kelsey Kreager

& Lynn Ersek

What is Digestion?

The process of breaking down food

– Provides nutrients

– Breaks down carbohydrates, fats, and proteins

Provides energy source (ATP)

The Mouth

• The first step in the digestive process

• Mastication occurs = chewing

•Saliva

• contains the enzyme amylase that breaks down

carbs

• creates a “bolus”

• softens food

EsophagusEsophagus

A muscular tube that moves food from the mouth to the stomach

“peristalsis” = muscular motion of the esophagus

Stomach!!!!Stomach!!!! Contains a HCl acid (pH 2)---walls are Contains a HCl acid (pH 2)---walls are

protected by thick layer of mucusprotected by thick layer of mucus

Parietal chief cell along wall Parietal chief cell along wall – Contain pepsides (enzymes)Contain pepsides (enzymes)

Digest proteins and carbsDigest proteins and carbs

Small Small Intestine/DuodenumIntestine/Duodenum

Duodenum Duodenum = beginning of sml. Intestine= beginning of sml. Intestine

Contains pH 7Contains pH 7 Enzymes digest FATSEnzymes digest FATS

Continue to digest proteins and carbsContinue to digest proteins and carbs

Villi line the small intestineVilli line the small intestine ABSORB NUTRIENTSABSORB NUTRIENTS

Duodenum VilliDuodenum Villi

Large Intestine/AppendixLarge Intestine/Appendix Reabsorbs H2O Reabsorbs H2O The bacteria =vitamin The bacteria =vitamin

productionproduction Encloses the small intestineEncloses the small intestine The appendix is a “finger-The appendix is a “finger-

like glandular piece of tissue like glandular piece of tissue that connects to the that connects to the beginning of the large beginning of the large intestine” intestine” ((http://kidshealth.org/parent/infections/sthttp://kidshealth.org/parent/infections/stomach/appendicitis.htmlomach/appendicitis.html).).

Rectum!!! (a.k.a. Mr. Hanky’s door)

Mr. Hanky exits the body.

Waste is deposited from the body.

Whatever is left from the digestive process.

Liver/Gallbladder/PancreasLiver/Gallbladder/Pancreas

Gallbladder (green)Gallbladder (green) Pancreas (orange)Pancreas (orange)- contains bile- contains bile -produces insulin -produces insulin

Liver (brown)Liver (brown)- detoxifies- detoxifies- stores “glycogen”- stores “glycogen” -insulin (stores)-insulin (stores) -glucagon (releases)-glucagon (releases)-immunity-immunity-helps make bile-helps make bile

Applications:Applications:Mouth:Mouth: cavitiescavities= bacteria infects “pulp” of tooth= bacteria infects “pulp” of tooth

endoscopyendoscopy= = tube w/ cameratube w/ camera

Stomach:Stomach: ulcersulcers= = holes in the stomach liningholes in the stomach lining

-causes: smoking, bacteria, stress-causes: smoking, bacteria, stress

Gallbladder:Gallbladder: gallstonesgallstones= = build up of cholesterol build up of cholesterol and salt and salt

Appendix:Appendix: appendicitisappendicitis—most common cause for children’s —most common cause for children’s abdominal surgery abdominal surgery

Pancreas:Pancreas: Type 1 diabetesType 1 diabetes= = pancreatic cells are pancreatic cells are destroyed (juvenile onset) destroyed (juvenile onset)

Type 2 diabetesType 2 diabetes= = “diet controlled”“diet controlled”

(obesity and diet)(obesity and diet)