Transcript 2006 Plano ISD, Plano, TX Digestive System © 2006 Plano ISD

© 2006 Plano ISD, Plano, TX
Digestive System
a coiled, muscular tube (6-9 meters
long) beginning with the mouth and
ending with the anus
© 2006 Plano ISD, Plano, TX
Digestion
Breaking down of food so the body
can use it.
2 forms of digestion
physical
© 2006 Plano ISD, Plano, TX
chemical
Forms of Digestion
Physical Digestion
Chemical Digestion
 mechanical
 chemical
breakdown of food
breakdown of food
into smaller particles by enzymes
 begins in mouth
by chewing
 begins in mouth
with saliva
 increases surface
area of food
 mostly occurs in
small intestine
© 2006 Plano ISD, Plano, TX
Physical Digestion
 mechanical
 begins in mouth
by chewing
© 2006 Plano ISD, Plano, TX
Chemical Digestion
 chemical
 begins in mouth
with saliva
Stages of Digestion

movement propels food through system

secretion


breakdown of food into
molecular sizes
food molecules passing
absorption
through intestinal walls

elimination removal of undigested food
release of digestive juices
digestion
© 2006 Plano ISD, Plano, TX
Primary
Digestive Organs
© 2006 Plano ISD, Plano, TX
begin the
mechanical
breakdown of
food
esophagus - transports
food to stomach through
the process of
stomach - muscular
peristalsis
organ that stores,
mixes, digests and
controls passage of
food
teeth
mouth
tongue
© 2006 Plano ISD, Plano, TX
Peristalsis
esophagus
food
stomach
© 2006 Plano ISD, Plano, TX
series of
involuntary
muscular
contractions
in the
esophagus
that
squeeze the
food down
to the
stomach
small intestines coiled tube from 3 6m long, the major
site for digestion and
absorption of
nutrients; contain villi
large intestines 1.5 m long tube,
absorbs water from
undigested material
anus - opening for
removal of feces
© 2006 Plano ISD, Plano, TX
Accessory
Digestive Organs
© 2006 Plano ISD, Plano, TX
salivary glands secrete a chemical
(enzyme) that breaks
down
into bile,
produces
liver -starch
glucose
which helps break down
fats in small intestines
gall bladder - stores bile
© 2006 Plano ISD, Plano, TX
pancreas - secretes
enzymes that break
down starches and
proteins
Accessory Digestive Organs
connected to stomach by ducts
liver
pancreas
gall bladder
© 2006 Plano ISD, Plano, TX
© 2006 Plano ISD, Plano, TX
ulcers
spot in stomach lining where cells
are destroyed, lining unprotected,
irritated by stomach acid
gastritis
swelling of stomach lining, caused
by irritating foods, alcohol, or
bacteria
acid
reflux
"back washing" of acid from the
stomach into the esophagus; also
called heartburn
© 2006 Plano ISD, Plano, TX
© 2006 Plano ISD, Plano, TX
1.
2.
3.
4.
© 2006 Plano ISD, Plano, TX
5.
6.
7.
8.
9.
10.
1. mouth
2. esophagus
3.
3. stomach
4. small intestine
5. large intestine
© 2006 Plano ISD, Plano, TX
6. anus
salivary glands
1.
liver
2.
3. bladder
gall
pancreas
4.
© 2006 Plano ISD, Plano, TX
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2.
3.
4.
5.
© 2006 Plano ISD, Plano, TX
6.
1.
2.
3.
4.
© 2006 Plano ISD, Plano, TX

Match the structure
with the number.




© 2006 Plano ISD, Plano, TX
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salivary
small
large
gall
esophagus
pancreas
stomach
liver
anus
bladder
intestine
intestine
glands


Match the function
with the number.
contains
major enzymes
organ forfor
secretes
transports
stores
mixes
the 4 undigestible
and
accessory
enzymes
food
stores
by
for
 digestion
stores
bile
theproduces
first
andchemical
absorption
contains
villi
bile
starch
digestive
peristalsis
food
breakdown
organs
of nutrients
of food
 breakdown

© 2006 Plano ISD, Plano, TX
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