2. Can you sort out the statements into
True and False?
Carbohydrates, proteins and fats are all made up of carbon,
hydrogen, nitrogen and oxygen.
Starch is a large carbohydrate molecule
Fats are made up of smaller units called amino acids
Proteins are made up of one or more glucose molecules
Starch molecules can be broken down by amylase.
Proteins are important for the growth and repair of cells
1
2
3
4
5
6
3. Parts of The Alimentary Canal
The alimentary canal (or gut) is the tube
within the body through which food passes
and is processed in various ways
o mouth
o oesophagus
o stomach
o small intestine
o large intestine
o anus
5. They are special proteins that behave as catalysts,
i.e., they accelerate each and every chemical
reaction in your body; otherwise, those chemical
reactions wouldn't take place, or would do at a very
slow pace. Enzymes are very specific and each
one can catalise only one chemical reaction: for
instance, the only thing that salivary amylase can
do is breaking the starch into maltose.
Enzymes
6. Role of the Mouth
Salivary gland
Salivary gland
Salivary gland
Saliva is mixed with
food during chewing
Teeth assist the
mechanical breakdown
of food
Saliva contains the
enzyme amylase which
starts the digestion of
food
Saliva contains mucus
that keeps the mouth
moist and lubricates
food for easier
swallowing
7. Muscles of the Alimentary Canal
Food has to be kept moving along the
alimentary canal whilst being mixed with
various juices
These actions are brought about by
muscles in the walls of the canal over
which a person has little or no conscious
control
8. Peristalsis
The squeezing action of muscles that is
used to move food along the
alimentary canal
Peri1.spl
• Peristalsis-1
• Peristalsis-2
9. Digestive Enzymes
What do the following enzymes
breakdown?
What do they break the large moleculs
down into?
Amlyases
Lipases
Proteases
10. Sites of production of main digestive
juices
Site of digestive juice
production
Main digestive juice
produced
Mouth Saliva
Stomach Gastric juice
Liver Bile (breaks down big fat
droplets into little fat
droplets
Pancreas Pancreatic juice
Small Intestine Intestinal juice
15. Tongue
The tongue is a muscle on the floor of the mouth that manipulates food for
chewing and swallowing (deglutition). It is the primary organ of taste, as
much of the upper surface of the tongue is covered in papillae and taste
buds.
20. In the stomach
Protein peptides
Broken down into amino acids later by
other proteases
pepsin
21. Chyme
The fluid food mass that is produced in
the stomach when the bolus undergoes
a second digestive stage.
22. Functions of liver
There are many functions of the liver. Some of the most important
are:
1. The production of bile
2. Detoxifying the body, i.e. breaking down alcohol and drugs
3. Breaking down excess amino acids to form urea
4. Converting glucose to glycogen for storage
5. Converting excess carbohydrates to fats
6. Storing vitamins
7. Storing minerals such as Iron, Copper, and Zinc.
8. Making plasma proteins such as fibrinogen which is used
in blood clotting
9. Making cholesterol which is used to form many hormones
10. Producing heat for the blood and body
23. Liver Facts
• Weighs about 1 pound.
• Carries out 1000s of functions per day.
• Effects the emotions.
• Cleanses the blood.
• Helps regulate blood sugar.
• Metabolizes fats.
• Synthesizes vitamin A.
• Breaks down toxic substances.
• Stores iron for the body.
• Stores glycogen (converted glucose).
• Metabolizes carbohydrates.
• Metabolizes proteins.
25. Bile
One of the five digestive juices. It is
produced by the liver, stored in the gall-
bladder, and it is greenish. It is necessary
mostly not to carry digestive enzymes to
the duodenum, but to transport bile salts to
the duodenum. The bile salts are
necessary to help the lipids to "dissolve" in
the chyle, forming small droplets, easy to
be attacked by the lipases. This process is
called emulsification.
32. After all the digestive enzymes have
done their work…
Glucose
Amino acids
Fatty acids
Glycerol
33. Finish the sentence….
Something new I learnt today was…..
Something I found difficult to understand
was…
The thing I need to revise from today’s
lesson is…