the digestive system cont’d…
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The Digestive System Cont’d…. A Closer Look at the Digestive Organs. Tongue Stomach Intestines. Understanding Enzymes. For food to move through the digestive pathways it must undergo changes. These changes would not be possible without the presence of enzymes. - PowerPoint PPT PresentationTRANSCRIPT
Primary Science Teaching Resources Monash Science Centre © 2006
The Digestive System Cont’d…
Primary Science Teaching Resources Monash Science Centre © 2006
A Closer Look at the Digestive Organs
Tongue
Stomach
Intestines
Primary Science Teaching Resources Monash Science Centre © 2006
Understanding Enzymes
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
Primary Science Teaching Resources Monash Science Centre © 2006
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
Reconstruct the Digestive System
Primary Science Teaching Resources Monash Science Centre © 2006
Nutrition and Exercise
Our bodies work hard for us what can we do to look after them?
Create Your Own Food Pyramid
Primary Science Teaching Resources Monash Science Centre © 2006
Nutrition
Primary Science Teaching Resources Monash Science Centre © 2006
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.
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.
Primary Science Teaching Resources Monash Science Centre © 2006
Calculation Your Energy Use in a Day
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 =
Sitting, watching TV or sleeping:
x 1.2 x (hours/24)
Classroom and homework:
x 1.5 x (hours/24)
Walking home from school, walking the dog, chores:
x 3 x (hours/24)
Exercise:
x 6 x (hours/24)
Primary Science Teaching Resources Monash Science Centre © 2006
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 hours6.069 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
She sleep: 12 hours 6.069 x 1.5 x (12/24) = 4.5518
An Example: Nicole’s Energy Balance
ADD them all together
2.2759 + 1.8966 + 1.1379 +0.3193 + 0.5689 + 4.5518 = 10.81
Multiply by 100010.81 x 1000 = 10 810 Kilo Joules (Joules is a measure of energy)
A elite soccer player uses about 16 500 KJ per day!
Primary Science Teaching Resources Monash Science Centre © 2006
A Realistic Understanding of Healthy