Download Digestive System Functions

Digestive System Functions
(The Alimentary Canal)
Joke of the Day:
Alimentary Canal:

The passage (including the esophagus,
stomach, and intestines) that food passes
through the body from mouth to anus
Types of Digestion
Mechanical (M): Chewing, churning of
food in stomache
 Chemical (C): Enzymes – From the
Mouth to the Small Intestine


Mouth (M,C) First Site of Digestion!
◦ (M) chewing
◦ (C) Salivary Amylase breaks down starch

Pharynx(M)
◦ Initiates swallowing

Esophagus (M)
◦ Transports food from mouth to stomach
through “Peristalsis”
 Peristaltic Waves: Waves of muscular contractions
that propel contents from one point to another

Stomach(M,C) (process food then transport)
◦ (M) churning to create a “Bolus”
 Bolus: Creamy paste that forms as the food in th
stomach is repeatedly mixed with gastric juices
◦ (C) HCl, pepsin kill bacteria and break down
proteins

Duodenum(C)
◦ 1ST 10 inches of small intestine. Bile secreted
here.

Jejunum(M,C)
◦ Next 8 feet of small intestine.
◦ Food absorption, enzyme action.

Ileum (M,C)
◦ “Terminal” portion of the small intestine
◦ Absorption of food, enzyme action

Ascending colon(M) Part 1 of the Large Intestine.
◦ Water, Nutrient and Electrolyte absorption

Transverse colon(M) Part 2 of the Large
Intestine
◦ Water, Nutrient and Electrolyte absorption

Descending colon(M) Part 3 of the Large Intestine
◦ Water, Nutrient and Electrolyte absorption

Sigmoid colon(M)
◦ Water and Electrolyte absorption

Rectum(M)
◦ Storage of feces

Anal canal(M)
◦ Sphincter for “waste management”
Warning – Prolapsed rectum
ahead!

Prolapsed rectum
Laproscopic Nissen Fundoplication
http://www.youtube.com/watch?v=_U8oz9xCamE