Food

Chemical element in food

  • Six chemical element

C H O N P S

(Carbon, hydrogen, oxygen, nitrogen, phosphorus & sulfur)

  • Dissolved salt

Na Mg Cl K Ca

(Sodium, magnesium, chlorine, potassium ¬ calcium)

  • Three trace element

Fe Cu Zn

(iron, copper & zinc)

Biomolecules - Are chemicals that are made inside a living thing

  • Carbohydrates

  • Proteins

  • Minerals

  • Lipids (fats)

  • Vitamins

  • Water

Carbohydrates

Contains the element: Carbon, hydrogen & oxygen

The general formula for a carbohydrate is

Cx(H20)y -  x & y are numbers

There are twice as many hydrogen molecules as oxygen molecules

Monosaccharides

These are

  • single sugar molecules

  • Simple sugar

  • Soluble in water

  • Sweet to taste

  • Smallest carbohydrate unit

Examples - Glucose, fructose

Found in - Fruits, sweets, energy drink..

Disaccharides

These are

  • Two monosaccharide sugar units joined together

  • Soluble in water

  • Sweet to taste

Examples - Sucrose, lactose, maltose

Found in - table sugar, milk, cereal

Polysaccharides

These are

  • Many monosaccharides sugar molecules joined together

  • Not soluble in water

  • Do not taste sweet

Example - starch (amylose), cellulose, glycogen

Found in- Bread pasta cereals

Three examples of polysaccharides

  • Starch - arranged in a chain easily diges - Storage polysaccharide in plants

  • Celluloose - Glucose molecules linked by cross -bonding - very strong and difficult to digest - make up the structure of cell wall

  • Glycogen - complex molecule with many chain bunched 

Metabolic role of carbohydrates

  • Glucose is broken down in respiration to release 

  • Glucose is made in photosynthesis