Download Complete Digestive System

Digestive
System
Types of Digestion
1) CHEMICAL DIGESTIONDigestion done using
enzymes and acid; purpose is to break food into
tiny microscopic building blocks, so they can be
absorbed into the blood stream.
2) PHYSICAL DIGESTIONbreaking food into smaller
chunks—uses teeth, and stomach grinding
*aka=mechanical digestion
Organs of the Alimentary Canal:
(the “tube” that food passes through)
1. Digestion begins in the mouth. Back of throat is the
epiglottistissue flap that separates the trachea
from the esophagus.
Organs of the Alimentary Canal:
(the “tube” that food passes through)
2. Secretions of the Salivary Glands
Organs of the Alimentary Canal:
(the “tube” that food passes through)
3. Esophagus: tube connecting the mouth and stomach
muscle contractions pushing food down are called peristalsis
Organs of the Alimentary Canal:
(the “tube” that food passes through)
4. Areas of the stomach:
-cardiac region
-fundic
-body
-pyloric
-lined with mucusa hole in mucus layer = ulcer.
Gastric Glands & Secretions
• Chief Cells
• secrete pepsinogen
• inactive form of pepsin
• Goblet Cells and Mucous Glands
• mucus
• protective to stomach wall
• Parietal Cells
•hydrochloric acid
•intrinsic factor—required for vitamin B12
• pepsinogen and HCl createpepsin
•protein splitting enzyme
Organs of the Alimentary Canal:
(the “tube” that food passes through)
5. Small intestine: contains small finger-like cells called
villi, which absorbs (sucks up) the small building
blocksamino acids; fatty acids & monosaccharides
-your s.i. is 18-24 feet long; it’s held together by a
membrane called the mesentery.
Organs of the Alimentary Canal:
(the “tube” that food passes through)
• Parts of the Small Intestines
-Duodenum
-Jejunum
-Ileum
Organs of the Alimentary Canal:
(the “tube” that food passes through)
6. Large intestines: absorbs water and makes/stores
feces
-feces is stored in the rectum (last part of the l.i.)
-feces is expelled out of the
body through the anus
-the non-functioning organ
called the appendix is
located at the junction of
the s.i. and the l.i.
ACCESSORY ORGANS OF DIGESTION:
(food does not pass through these organs)
1. Liver: makes bile to help digest fats; has 3 lobes
-largest internal body organ
-covers the stomach, pancreas, and top of the l.i.
-located below the diaphragm
-brown in color
-the liver dumps its bile into the s.i.
ACCESSORY ORGANS OF DIGESTION:
(food does not pass through these organs)
2. Pancreas: the enzyme factory of the body—makes
enzymes used in chemical digestion
-dumps its enzymes into the s.i.
ACCESSORY ORGANS OF DIGESTION:
(food does not pass through these organs)
3. Gall Bladder: stores extra bile from the liver.
11. Mouth: Teeth and
Tongue help move food
around—physical
digestion
1. Salivary gland:
Chemical digestion—
breaks down starch using
amylase
2. Esophagus—moves food
to stomach
5. Liver: aids S.I. in
chemical digestion
6. Gall bladder: stores bile
7. Large Intestines: absorbs
water and stores feces in
rectum
8. Appendix: no longer
functional
9. Rectum/Anus: store and
expels waste
3. Stomach: physical and
chemical digestion occur
4. Pancreas: aids S.I. in
chemical digestion
10. Small Intestines:
Chemical digestion and
absorbs nutrients