Theme 1 : b) Nutrition

Food Classification 

Factor that Influence a Person's needs for a Balance Diet

ⅰ) Sex :
  Men requiring more energy than women at the same age and body size because men are more active

ⅱ) Age: 
   Babies, children and teenagers require more energy because they more active and they life    
   process are faster

ⅲ) Body sized : 
   Big sized individuals require more energy compared to small sized individual 

ⅳ) Physical Activity :
 Individual with heavy work use more energy compared to another who does light work  

ⅴ) Weather : 
 Individuals living in place with cold weather require more energy compare in 
  place with warm weather  

Human Digestive System 

- Digestion is the process of breaking down complex food to simple molecules for absorption the blood circulatory system
- Digestion take place in two stage :
         ⅰ) physical digestion ➯big pieces of food are broken down into smaller pieces
                                                by teeth
        ⅱ) chemical digestion➯enzymes break up complex food molecules into smaller 
                                              molecules
- Enzymes are protein that speed up the process of digestion. Enzymes break up complex food molecules to smaller and simple molecules

✱ Characteristic of enzymes
          a) enzymes are small quantities only
          b) enzymes are not destroyed at the end of digestion
          c) specific enzymes act only in specific acidic or alkaline conditions
          d) specific enzymes act only on specific foods
          e) enzymes function best at normal body temperature (37℃)
          f) enzymes are destroyed at high temperature