2. :DUODENUM- the part of the small intestine
:PEPSIN- the enzyme in the stomach
:GALL- the...bladder stores and concentrates the
bile
:ENZYMES- the organic catalysts that converts food
into simple substances that the body can utilize
:STOMACH- the organ where protein is first
chemically digested
:MOUTH- the anterior opening of the digestive
system
:BILE- the fluid secreted by the liver
:ESOPHAGUS- the muscular tube that conveys food
down to the stomach
:ANUS- the posterior opening of the digestive
3. DIGESTION
-the process by which food is broken down into
small molecules that the body can use to
nourish the cells. As the food enters the body,
the food undergoes two phases of digestion.
2 Phases of Digestion:
MECHANICAL PHASE:
the food is broken down into small pieces
by the process of chewing or mastication
CHEMICAL PHASE
the food is acted upon by the chemical
substances called enzymes that are secreted
together with the digestive juices
4. 2 main parts:
Alimentary tract Accessory organs
Mouth Salivary glands
Pharynx Liver
Esophagus Gall bladder
Stomach Pancreas
Small intestine
Large intestine
Rectum
Anus
5. MOUTH
Digestion begins in mouth or oral cavity.
Teeth- break down food into small pieces
Tongue- a muscular organ that mixes the
food with the saliva, aids in swallowing.
Ducts of salivary glands- secrete the
saliva that lubricates food
Palate- forms the roof of the mouth
6. PHARYNX or THROAT
Located immediately posterior to mouth.
About 5 to 6 inches
Common passageway for digestion and respiration
ESOPHAGUS
Muscular tube through which food passes from
pharynx to stomach
Peristalsis- wave-like contraction
STOMACH
Expanded organ located between the esophagus and
small intestine.
Muscular, elastic, pear-shaped organ.
About 30.5 cm long and 15.2 cm wide
3 FUNCTIONS:
Storage of the swallowed food
Mixes the food with the digestive juice it produces
Conveys its contents slowly into small intestine
7. SMALL INTESTINE
Organ of complete digestion and
absorption.
It secretes the enzymes that change
food materials into their simplest
contents
Longest organ of the digestive
system
About 6 meters long and 2.5 cm in
diameter
3 sections
Duodenum (25 cm long)
Jejunum (1.4 meter long)
8. LARGE INTESTINE or COLON
The next organ after the small intestine.
About 1.5 meter long and 5 cm in diameter.
3 FUNCTIONS:
Temporary stores fecal materials
Absorbs vitamins produced by certain
symbiotic bacteria in the colon
Reabsorbs water from the undigested residue
3 DISTINCT PARTS:
Ascending colon
Traverse colon
Descending colon
9. RECTUM
Located at the distal end of the sigmoid
colon(the distal end of the descending
colon)
About 8 inches long
Basically serves as a warehouse for the
undigested residue or feces.
ANUS or ANAL CANAL
Located at the end part of the rectum
Exit point for fecal materials
10. Accessory Organs of Digestion
Salivary Glands
located in the mouth
three types: parotid, sublingual, submandibular
saliva: combination of watery fluid(serous fluid) and
mucus
Liver
largest organ of the body.
located on the right side of the upper abdomen
production of bile from bilirubin
2 functions of Bile in digestion:
emulsifies fats
neutralizes the acidity of the partly digested
food(chyme)
About 500 to 1000 mL of bile is stored in our liver
daily
Pancreas
