Download L4 The LARGE INTESTINE

L4 Outline
1.  Mark Enzymes worksheet
2.  Notes on large intestine
3.  Notes on problems with large intestine
1.  Fibre
2.  Diarrhoea
3.  Constipation
4.  Finish video on digestion
L4 Quiz Small Intestine
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1. What is each number?
1.  Duodenum
or small
intestine
2.  Pancreas
3.  Stomach
4.  Cardiac
sphincter or
esophagus
L4 Quiz Small Intestine
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2. What green liquid is inserted into the upper small
intestine?
bile
L4 Quiz Small Intestine
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3. What enzyme is secreted by the small intestine?
Lipase
L4 Quiz Small Intestine
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4. What are the two main jobs of the small intestine?
Digestion and
absorption
L4:The Digestive Process - Defecation
How does the body process food?
The large intestine is about
1.5 meters long, containing
undigested material including
fiber, bacteria and other wastes
that have been passed from the
small intestine. It's here, that
water is extracted (recycled)
and the waste material is finally
processed before elimination. L4 The LARGE INTESTINE
The large intestine (colon)
extends from the ileocecal
sphincter to the anus; the
medical specialty that deals
with the diagnosis and
treatment of disorders of the
rectum and anus is called
Proctology.
L4 The LARGE INTESTINE
Its subdivisions include the
cecum, colon, rectum,
and anal canal.
cecum
rectum
anal canal
colon
L4 The LARGE INTESTINE
Processes occuring in the large intestine
•  bacterial breakdown of food
•  bacteria synthesize some vitamins which
are absorbed
•  water is absorbed
•  electrolytes are absorbed
L4: The LARGE INTESTINE
Feces consist of
• water
• inorganic salts
• sloughed-off epithelial (skin) cells
• bacteria
• products of bacterial decomposition
• undigested parts of food
L4 The LARGE INTESTINE
Although most water
absorption occurs in the
small intestine, the large
intestine absorbs enough to
make it an important organ
in maintaining the body’s
water balance.
L4 The LARGE INTESTINE
The elimination of feces from the rectum is called
defecation.
Defecation is a reflex action aided by voluntary
contractions of the diaphragm and abdominal muscles.
¨ Diarrhea refers to frequent defecation of liquid
feces. It is caused by increased motility of the intestine
and can lead to dehydration and electrolyte
imbalances.
¨ motility of=movement of food through
L4 The LARGE INTESTINE Problems
Constipation refers to infrequent or difficult defecation and
is caused by decreased motility of the intestines, in which
feces remain in the colon for prolonged periods of time.
Caused by
• low fibre
• resisting
defecation
• low excercise
• low liquid intake
• medications
Can cause
• hemorrhoids
• anal fissure
• rectal prolapse
• fecal impaction
• vomiting (uh oh)
Prevent by
• eating high fibre
• lots of liquids
• excercise
• use the toilet
when you get the
urge
L4 The LARGE INTESTINE
Dietary fiber (bulk of roughage)
Two types soluble and insoluble. Both
types affect the speed of food passage
through the GI tract.
Benefits
• protects vs colon cancer
• lower blood cholesterol
• reduces constipation
• prevents diverticulosis
L4 The LARGE INTESTINE
¨ 1. Watch video on digestive system