human digestive system.

1. HUMAN
DIGESTIVE
SYSTEM

2. What is digestive
system?
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Digestive system is a group of organs and associated digestive
glands that take part in ingestion of food , it’s crushing ,
digestion , absorption of digested materials and egestion of
waste.

3. Digestion
Flowing phases are Included in the process:
1. Ingestion
2. Movement
3. Mechanical and Chemical Digestion
4. Absorption
5. Elimination

4. Digestive System Organization
 Structures in digestive system:
• Mouth
• Pharynx
• Esophagus
• Stomach
• Small intestine
• Large interstine.
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5. Mouth
O Teeth mechanically break
down food into small
pieces. Tongue mixes food
with saliva (contains
amylase, which helps break
down starch).
O Epiglottis is a flap-like
structure at the back of the
throat that closes over the
trachea preventing food
from entering it.

6. DigestionO Types
O Mechanical (physical)
O Chew
O Tear
O Grind
O Mash
O Mix
O Chemical
O Enzymatic reactions to improve digestion of
O Carbohydrates
O Proteins
O Lipids

7. Esophagus
O Approximately 10” long
O Functions include:
1. Secrete mucus
2. Moves food from the throat to the
stomach using muscle movement
called peristalsis
O If acid from the stomach gets in here
that’s heartburn.

8. Stomach
O J-shaped muscular bag that stores the food
you eat, breaks it down into tiny pieces.
O Mixes food with digestive juices that contain
enzymes to break down proteins and lipids.
O Acid in the stomach kills bacteria.
O Food found in the stomach is called chyme.
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9. Liver
Directly affects digestion by producing
bile
O Bile helps digest fat
• filters out toxins and waste including
drugs and alcohol
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10. Gall Bladder
O Stores bile from the liver,
releases it into the small
intestine.
O Fatty diets can cause
gallstones

11. Pancreas
O Produces digestive enzymes to
digest fats, carbohydrates and
proteins
O Regulates blood sugar by
producing insulin

12. Small Intestine
O Small intestines are roughly 7 meters long
O Lining of intestine walls has finger-like
projections called villi, to increase surface
area.
O The villi are covered in microvilli which further
increases surface area for absorption.
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14. Small Intestine
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O Nutrients from the food pass into the
bloodstream through the small
intestine walls.
O Absorbs:
O 80% ingested water
O Vitamins
O Minerals
O Carbohydrates
O Proteins
O Lipids
• Secretes digestive enzymes

15. Large Intestine
O About 5 feet long
O Accepts what small intestines don’t
absorb
O Rectum (short term storage which holds
feces before it is expelled).

16. Large Intestine
O Functions
O Bacterial digestion
O Ferment carbohydrates
O Protein breakdown
– Absorbs more water
– Concentrate wastes

17. Accessory Organs
O Not part of the path of food,
but play a critical role.
O Include: Liver, gall bladder,
and pancreas