1. Food

2. Why do we need food? To supply energy to live, move and survive
To grow, and to repair damaged cells and tissues in our body.
To keep warm.
To prevent diseases.

3. Breads and Cereal Group 6 or more servings
FOOD PYRAMID
Fats, Oils and Sweets use occasionally
Milk Group 2 servings
Meat Group 2 servings
Fruit Group 2-4 servings
Vegetable Group 3-5 servings
Breads and Cereal Group 6 or more servings

4. Balanced Diet
A balanced diet contains the right amount of each of the different types of food

5. NUTRIENTS AND THEIR FUNCTIONS
CARBOHYDRATES
for energy
Protein
for growth and repair
FATS
for energy and warmth
VITAMINS and MINERALS
to keep us healthy and to prevent diseases

6. Carbohydrates
Starch
Sugar
Fibre

7. Test for starch

8. To test for the presence of Starch
Apparatus
Iodine in dropper and Starch Sample ie Potato or bread
Method
Using the dropper , place a few drops of iodine on your sample
Note the change in colour if any
Result
The sample turned _______
Conclusion
Iodine turned from brown to Blue/Black. This indicates that starch is present.

10. Fats
Insulation
Energy
Protection

11. To test for the presence of Fats
Apparatus
Brown paper and fat sample
Method
Place a small amount of butter on a piece of brown paper
Allow to dry
Hold the paper up to the light
Result
The spot turns _______
Conclusion
Translucent Spot indicates that fat is present

12. Proteins
Growth and repair of cells
Make enzymes and hormones

13. Vitamins
C to prevent scurvy
D to prevent rickets

14. Minerals
Iron to prevent anaemia
Calcium bone & teeth

17. Water
Solvent
Transportation of substances around body

18. Food Types and its Functions
Sources
Carbohydrates
Starch
Sugars
Fibre
To provide energy
To prevent constipation
Fruits & jams
Potato,bread,rice & Pasta
Cereals & Green Veg
Proteins
Growth and repair of cells
Fish, Milk, Nuts & Meat
Fats
Insulation
Milk, Butter & Oil
Vitamins
C to prevent scurvy
D to prevent rickets
Oranges & Lemons
Skin& Dairy products
Minerals
Iron to prevent anaemia
Calcium bone & teeth
Liver, Meat ,Veg
Milk, cheese
Water
Solvent
Transportation of substances around body
Tea

19. Scurvy
Definition
A condition characterized by general weakness, anaemia, gum disease (gingivitis), and skin haemorrhages resulting from a lack of Vitamin C in the diet.

21. Prevention?!

24. Rickets

25. Rickets
Deficiency in Vitamin D.
Prevention??

26. Food Tests

28. To test for the presence of Reduced Sugars
Apparatus
Glucose solution, Benedicts solution, test tubes, water bath
Method
Set up the test tube rack, with 4 test tubes A,B,
Place 5mls of water in A and 5mls of glucose solution into B
Add Benedicts solution to A and B
Place test tubes into a beaker of hot water on a hot plate
Note Results
Result
The B solution _______
The D solution turns _______
Conclusion
Brick red colour in D indicates that reduced sugars is present

30. Examples of Protein

31. Examples of Protein

32. To test for the presence of Protein
Apparatus
Test tubes and test tube rack
Sodium Hydroxide Solution & Copper Sulphate Solution & Milk
Method
Add 5cm3 of milk and water to two separate test tubes
Using the dropper add Sodium hydroxide solution( Colourless) and then Copper Sulphate solution ( blue)
Note the change in colour if any
Result
The milk sample turned _______
Conclusion
Violet/Purple indicates that protein is present

33. Examples of Fat

34. Energy values Different foods contain different amounts of energy.
These amounts are known as Energy Values.
Energy is measured in Joules (J).
However energy values of a food can be measured in Kilojoules per 100 gram.
All foods are supposed to display nutritional information on their packets; the table of information on the right was given on a packet of wheat bran.

37. To show that there is energy in food: Conversion of chemical energy to heat energy
Apparatus
Beaker, tripod, bunsen burner, gauze, thermometer, mounted needle & peanut.
Method
Place 100mls of cold water into the beaker on the tripod with the gauze
Note the temperature using the thermometer
Place the peanut on the mounted needle and hold under a bunsen flame until it is alight
Hold the burning peanut under the beaker
After the peanut is finished burning , note the new thermometer of the water
Result
The temperature of the water has risen
Conclusion
As the peanut burns chemical energy is converted into heat energy which results in a rise in the temperature of the water

38. Summary The range of food that an animal eats is its DIET
Functions of food include tp provide energy and to provide material for growth
Food types: Carbohydrates, Fats, Proteins, Minerals and Vitamins.
Foods content chemical energy
The amount of energy present in food per 100g is given on the food label
A Balanced diet contains the correct amount of all of the food groups
A diet must be balanced in terms of energy
A food pyramid recommends the daily intake of each of the different food groups