3. Why nutrition is important ?
• All living things need energy to continue their
life processes .
• This energy comes from the food we eat.
• Food is also needed for growing and repairing
worn-out body cells.
• Energy is released from food by the process of
respiration.
Carbon
Food oxygen Energy Water
dioxide
4. The food can be classified into seven
classes:
Carbohydrate Vitamins
6. Proteins
• Sources:
fish, eggs, milk, beans
• Functions:
- For growth and the repair of worn- out cells.
- Prevent Kwashiorkor.
7. Fats
• Sources:
Cheese, butter, cooking oil, margarine
• Functions:
To provide twice as much heat energy as
carbohydrates and to insulate the body
against heat loss.
8. Vitamins
• Sources:
Fruits, vegetables
• Functions:
to maintain health and to prevent various
deficiency of disease.
9. Minerals
• Minerals are needed for normal growth and
development of the body. They are needed in
small quantities.
• Sources:
For eggs, milk, fish
10. Fibre or roughage
• Sources:
Vegetables, fruits, cereals
• Functions:
To prevent constipation and to help in
peristalsis.
Constipation = sembelit 便秘
11. Water
• Sources:
Water, fruits, beverages
• Functions:
To maintain the liquid condition of the cells
and medium of various chemical reactions.
12. Facts About Vitamins
Water •Vitamin B
soluble •Vitamin C
Vitamins
•Vitamin A
Fat •Vitamin D
soluble •Vitamin E
•Vitamin K
13. • Functions:
Promotes good night vision, maintains healthy
skin.
• Effect of deficiency:
Night blindness, dry scaly skin
14. • Functions:
Maintains healthy skin and nervous system.
• Effect of deficiency:
Beriberi, pellagra
15. • Functions:
Maintain healthy skin. It also promotes wound
healing.
• Effect of deficiency:
Scurvy, difficulty in healing wounds.
16. • Functions:
Helps the body absorb calcium and
phosphorus.
• Effect of deficiency:
Rickets
17. • Functions:
i) Helps in formation of red blood cells and
helps the body use vitamin K.
ii) Improve male fertility.
• Effect of deficiency:
Sterility Sterility = Kemandulan 不育症
18. • Functions:
Promotes blood clotting
• Effect of deficiency:
Blood unable to clot.
19. Calcium
• Sources:
Cheese, milk, eggs
• Functions:
Calcium helps form and maintain healthy
teeth and bones.
Helps blood clotting and construction of
muscles.
• Effects of deficiency:
Rickets, osteoporosis
20. Sodium
• Sources:
Common salt, salted eggs, soy sauce…
• Functions:
Regulate blood pressure , maintains the
function of muscles and nerves.
• Effects of deficiency:
Muscular cramps
21. Iron
• Sources:
Liver, eggs, spinach, lean red meat, salmon…
• Functions:
Formation of haemoglobin.
• Effects of deficiency:
Anaemia
Anaemia = anemia 贫血
22. Iodine
• Sources:
seafood, leafy vegetables
• Functions:
Synthesis of thyroxine ( hormone that increases the
rate of cell metabolism and regulates growth)
• Effects of deficiency:
Goitre
23. Phosphorus
• Sources:
Milk, cheese, eggs, meat, vegetable…
• Functions:
Formation of bones and teeth.
• Effects of deficiency
Rickets
24. Potassium
• Sources:
meat, nuts, bananas…
• Functions:
Maintain body fluid, proper function of nerves,
regulation of heartbeat.
• Effects of deficiency:
Weak muscles, paralysis
Paralysis is loss of muscle function for one or more muscles.
26. Test for starch
(a) Add a few drops of iodine solution to a test
tube containing 3 ml of starch solution.
(b) The starch solution turns dark blue in colour.
27. Test for glucose
(a) Add about 1 ml of Benedict's solution to a
test tube containing 3 ml of glucose solution.
(b) Heat the mixture in the test tube using a
water bath.
(c) A brick-red precipitate is formed.
28. Test for proteins
(a) Add a few drops of Millon's reagent to a test
tube containing 3 ml of albumen solution.
(Albumen contains proteins)
(b) Heat the mixture in the test tube using a water
bath.
(c) A red precipitate is formed.
29. Test for fats
• Pour about 20 mm (depth) ethanol in to test
tube
• Add one drop of vegetable oil, and shake the
tube sideways until the oil dissolves in the
alcohol.
• Add 2ml of water in the test tube.
