The Digestive System Cont’d…
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A Closer Look at the Digestive Organs
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Tongue
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Stomach
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Intestines
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Understanding Enzymes
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For food to move through the
digestive pathways it must
undergo changes.
These changes would not be
possible without the presence
of enzymes.
Enzymes ensure that the
changes occur at an
appropriate rate.
As a result our body functions
effectively in a timely manner.
Enzymes are biological
catalysts
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Reconstruct the Digestive System
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Break Bread into four pieces
Put into plastic zip lock bag
Add water
Mechanically break bread
Add powder enzyme
Continue to breakdown the bread
Pour through chux cloth
Pour through sponge
Shape the remaining material
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Nutrition and Exercise

Our bodies work hard for us what can we
do to look after them?
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Create Your Own
Food Pyramid
Nutrition
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Food, Energy and Exercise

We need food for energy.
 Our body uses energy to function.
 The way our body uses this energy is called metabolism
 We can measure how much energy we use for normal body functioning
and this is called our basal metabolic rate or BMR.
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When we exercise additional energy is needed.
 This energy initially comes carbohydrates.
 When our carbohydrates run out the body uses fats.
 Once the fats run out the body uses proteins.
 Using protein for energy is very dangerous because it breaks
down our bodies, so we need to eat enough food including
carbohydrates especially when exercising.
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Calculation Your Energy Use in a Day
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Basal Metabolic rate ( ) –
the amount of energy your
body uses to function. This
energy is used to ensure
your heart pumps and your
lungs expand and other
bodily function occur.
Male
(0.074 x weight (65kg)) + 2.754
= 7.564 =
Female
(0.056 x weight (55kg)) + 2.989
= 6.069 =
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Sitting, watching TV or
sleeping:
x 1.2 x (hours/24)
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Classroom and homework:
x 1.5 x (hours/24)
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Walking home from school,
walking the dog, chores:
x 3 x (hours/24)
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Exercise:
x 6 x (hours/24)
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An Example: Nicole’s Energy Balance
Nicole is a young university student. To measure her BMR we need to calculate how much energy she
uses in day depending on the type of activities she does using the calculations from the previous slide.
She plays Sport: 1.5 hours
BMR x 6 x (1.5/24)
=6.069 x 6 x 0.0625
=2.2759
She goes to University: 5 hours
6.069 x 1.5 x (5/24) = 1.8966
She does Homework: 3 hours
6.069 x 1.5 x (3/24) = 1.1379
She eats Eat: 1 hour
6.069 x 1.5 x (1/24) = 0.3793
She watches TV: 1.5 hours
6.069 x 1.5 x (1.5/24) = 0.5689
ADD them all together
2.2759 + 1.8966 + 1.1379 +0.3193 +
0.5689 + 4.5518 = 10.81
Multiply by 1000
10.81 x 1000 = 10 810 Kilo Joules (Joules
is a measure of energy)
A elite soccer player uses about 16 500 KJ
per day!
She sleep: 12 hours
6.069 x 1.5 x (12/24) = 4.5518
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A Realistic Understanding of Healthy
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