hi

1. The digestive system

2. Notice of Use Restrictions
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 Materials are included in accordance with the [U.S.]
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© EDMAN YOST, J. (1999), Copyright Chaos - An Educator's Guide to Copyright Law and “Fair Use”, Intel Teach
to the Future CD

3. Lesson 1
• OB6 Identify and locate the major parts of
the digestive system including: the mouth,
oesophagus, stomach, liver, pancreas,
small intestine, and know their functions

4. Lesson 2
• OB7 Identify molars, premolars, canines
and incisors, and describe their functions

5. Lesson 3
• OB8 Investigate the action of amylase on
starch; identify: the substrate, product and
enzyme

6. Lesson 1
What happens during digestion? The
organs involved in the process

7. The Cell
What happens in digestion?

8. 5 Stages of Digestion
• Ingestion
• Digestion
• Absorption
• Assimilation
• Egestion
• http://www.learning-is-
fun.co.uk/biology/nutrition.html
• In
• Down
• Around
• And
• Eject

9. • Ingestion: Food taken into mouth
• Digestion: Food broken down by teeth and
digestive enzymes
• Absorption: into bloodstream
• Egestion: Undigested
material egested through anus

10. Large
Molecule
Enzymes
A
B
S
O
R
P
T
I
O
N
An Overview

11. Importance of digestion
• Digestion: Break down of large food
molecules into small molecules
• Types of digestion:
– Physical
– Chemical

12. The Mouth
• Function: Chew food to break down
into smaller molecules
– Teeth

13. Teeth
• Four types of
teeth:
1. Incisors
2. Canines
3. Pre – Molars
4. Molars
Incisors
Canines
Premolar
Molar

14. Biting
and
Cutting
Incisor
Grasping
and
Tearing
Canine
Grinding
and
Crushing
Pre - Molar
Grinding
and
Crushing
Molar

15. Digestive Organs
• Oesophagus
• Stomach
• Small Intestines
• Large Intestines
• Pancreas
• Liver
Name some digestive
organs…..

16. The parts of the digestive system
• The mouth
• The oesophagus
• The stomach
• The small intestine
• The large intestine

17. The Oesophagus
• Function: to take food from mouth
to stomach by muscular action called
peristalsis
= Food particle
Oesophagus

18. Stomach
• Store food
• Mix food with juice
• Kill bacteria in food

19. Small Intestine
• Complete digestion of food
• Absorb digested food into bloodstream

20. Large Intestine
• To absorb water from the waste food,
solidifying the faeces

21. Liver
• The liver makes bile
• Function of bile
– to dissolve fats
– neutralise acid from
the stomach

22. The Pancreas
• Sends a liquid into the
small intestine
– digestive enzymes to
digest starch, proteins
and fats

23. Lesson 3
Practical Class

24. Enzymes
• Biological catalysts that break down food

25. To investigate the action of
amylase on starch
Starch
sol.
Starch sol.
& amalyse
A B
A B
37°
10mins
Iodine

26. The Action of Amylase on Starch
Use the set up above to investigate!

27. End Products of digestion
• Carbohydrate
• Protein
• Fats
• Simple sugars
• Amino acids
• Fatty acids and
glycerol

28. Assessment
Students must attempt all
questions!

29. Question 1
• (a) What are the functions of the digestive
system
• (b) Name the chemicals that digest food

30. Question 2
• Name the part
labelled A to E.
• Name the parts
labelled F and G

31. Question 4
• Follow the food as it
passes through the
digestive tract and
explain the process of
digestion.

32. • Identify type of teeth marked A,B and C.
• Give the function of each.
A B C

33. Chapter Assessment
1. An enzyme is a biological _____________
2) Taking food into the mouth is known as ____________
3) Explain the difference between physical and chemical digestion.
Give one example of each type.
4) What is the name given to the process whereby food is pushed
along the alimentary canal
5) List the two major functions of the large intestine ?.
6) The oesophagus carries the food from the ________
to the __________

34. Bibliography
• http://www.chemistry.wustl.edu/~edudev/LabTutorials/HI
V/images/enzyme.jpg
• www.calalumni.ch/images/ 031025_basel_meeting/...
• http://science.waltermack.com/smack/yr8biol/digestion2.
gif
• http://medicalimages.allrefer.com/large/gelatin-capsule-
in-stomach.jpg
• http://www.becomehealthynow.com/images/organs/diges
tive/sm_intestine.jpg
• http://www.cindys-friends.com/images/pic_intestine.jpg
• http://laxmi.nuc.ucla.edu:8000/NM-
Mediabook/figures/GI/liver/liver_ant.gif

35. Bibliography
• http://gxs.home.texas.net/work_samples/pancreasf/panc
reas.gif
• http://bimari-jankari.mla.iitk.ac.in/html/b_digest.htm
• http://files2.turbosquid.com/Preview/Content_on_8_10_2
005_06_45_00/mr_fastsss_teeth_various_poses.pnge9a
81577-7091-47bc-992e-835a2061e3dcLarge.jpg
• www.ivansanford.com/il_bloodstream.html
• Clip art
• Shea Mullally: Less stress more success – science
• Michael O’ Callaghan: Exploring Science: Edco