The digestive system is made up of organs and glands that work together to break down food, absorb nutrients, and remove waste. It includes the mouth, esophagus, stomach, small intestine, large intestine, liver, gallbladder and pancreas. Food is ingested, mechanically and chemically broken down, absorbed in the small intestine, and eliminated as waste in the large intestine and rectum. The liver, gallbladder and pancreas produce enzymes and bile that help digest fat and break down nutrients.

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