i ain't the one who made this but hope it helps (credits to my classmates in SLSU Lucban) *hi

1. Animal and
Human Digestion
2006-2007

2. Digestive System – Objectives
 Describe and understand the basic
functions of the primary components of
the digestive system.
 Compare the functions and locations of
the digestive organs in man and
animals.
 Differentiate between and identify
digestive systems of man and animals.

3. Digestion
 Digestion is the breakdown
of large, complex organic
molecules into smaller
components that can be
used by the body.
 Molecules need to be small
enough to diffuse across
plasma membranes.

4. HUMAN DIGESTION

5. Four Components of Digestion
 Ingestion – this is the consumption of
or taking in of nutrients.
 Digestion – the chemical breakdown of
large organic molecules into smaller
components by enzymes.
 Absorption – the transport or delivery
of digested nutrients to body tissues.
 Egestion – the elimination of food
waste materials from the body.

6. Ingestion
 Food enters the
human digestive tract
through the mouth or
oral cavity.
 Humans are
considered chunk
feeders because they
consume chunks of
food that are then
mechanically broken
down.

8. Mouth
 Teeth
mechanically
break down food
into small pieces.
Tongue mixes
food with saliva
(contains
amylase, which
helps break down
starch).

9. Mouth
 Epiglottis is a
flap-like structure
at the back of the
throat that closes
over the trachea
preventing food
from entering it.

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

11.  Esophagus: muscular tube that connects
mouth to stomach
– Peristaltic waves send feed down the
esophagus, (muscle contractions).
– Reverse Peristalsis = blowing chunks
– The cardia, located at the end of the
esophagus prevents feed in the stomach from
coming back into the esophagus. ( non-
ruminants only)

12. Stomach
 J-shaped muscular bag that
stores the food you eat,
breaks it down into tiny pieces.
 Mixes food with digestive
juices that contain enzymes to
break down proteins and
lipids.
 Acid in the stomach kills
bacteria.
 Food found in the stomach is
called chyme.
12

13. Small Intestine
 Small intestines are roughly
7 meters long
 Lining of intestine walls has
finger-like projections called
villi, to increase surface
area.
 The villi are covered in
microvilli which further
increases surface area for
absorption.
13

14. Small Intestine
 Nutrients from the food pass
into the bloodstream through
the small intestine walls.
 Absorbs:
– 80% ingested water
– Vitamins
– Minerals
– Carbohydrates
– Proteins
– Lipids
* Secretes digestive enzymes
14

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

16. Large Intestine
 Functions
– Bacterial
digestion
• Ferment
carbohydrat
es
• Protein
breakdown
– Absorbs more
water
– Concentrate
wastes

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

18. Liver
 Directly affects
digestion by
producing bile
– Bile helps digest fat
• filters out toxins
and waste
including drugs
and alcohol
18

19. Gall Bladder
 Stores bile from
the liver,
releases it into
the small
intestine.
 Fatty diets can
cause gallstones

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

21. Understanding the Digestive
Systems
 Ruminants  Non-ruminants

22. A RUMINANT ANIMAL
 Has four distinctive compartments in its
stomach, which swallows its food essentially
unchewed, regurgitates, and chews it
thoroughly and reswallows it again.
 Examples include cattle, sheep, goats, deer,
rhinos, and elk.

23. Rumination (regurgitation)
 After rumen if full, it lies down to ruminate
(chew its cud)
 Cattle spend from 5-7 hours ruminating,
broken up into 6-8 periods
 Regurgitation is the process of forcing the
feed back into the mouth for chewing
 Done through a series of muscular
contractions and pressure in the rumen and
reticulum

24. A NONRUMINANT ANIMAL
 Has a single compartment in its
stomach, which swallows its food
after chewing and does not
regurgitate its food.
 Examples include pigs, humans,
bears, and dogs.

25. Nonruminant Digestion
 food is swallowed
directly into the
single stomach
compartment
 it is mixed with
digestive juices

26. What do animals need to live?
 Animals make energy
using:
– food food
– oxygen
 Animals build bodies
using:
– food for raw materials ATP
• amino acids, sugars, O
2
fats, nucleotides mitochondria
– ATP energy for
synthesis

27. How do animals get their food?
filter feeding living in your food
fluid feeding bulk feeding

28. Getting & Using Food
 Ingest
– taking in food
 Digest
– mechanical digestion
• breaking up food into smaller pieces
intracellular
– chemical digestion digestion
• breaking down food into molecules
small enough to be absorbed into
cells
• enzymes
 Absorb
– absorb nutrients across cell membranes
• diffusion
• active transport
 Eliminate
– undigested material passes out of body extracellular
digestion

29. Different diets; different bodies
 Adaptations of herbivore vs. carnivore
– teeth
– length of digestive system
– number & size of stomachs

30. Teeth
 Carnivore
– sharp ripping
teeth
– “canines”
 Herbivore
– wide grinding
teeth
– molars
 Omnivore
– both kinds of
teeth

31.  Herbivores &
Length of digestive
omnivores system
– long digestive
systems
– harder to digest
cellulose (cell
walls)
• bacteria in
intestines help
 Carnivores appendix
– short digestive
systems
– protein easier to
digest than
cellulose

32. Fun Facts
• HOW LONG ARE YOUR INTESTINES? At
least 25 feet in an adult. Be glad you're not a
full-grown horse -- their coiled-up intestines
are 89 feet long!
• Food drying up and hanging out in the
large intestine can last 18 hours to 2 days!
• In your lifetime, your digestive system may
handle about 50 tons!!

34. Write the name of each colored
organ:
 Green:
 Red:
 Pink:
 Brown:
 Purple:
 Green:
 Yellow:

35. How’d you do?
 Green: Esophagus
 Red: Stomach
 Pink: Small
Intestine
 Brown: Large
Intestine
 Purple: Liver
 Green: Gall Bladder
 Yellow: Pancreas
Great Job!