Digestive System

• We get our energy from our food so that we can perform various functions every day. • We all need/needed to grow. • Our bodies need to repair themselves and replace worn out tissue. • Our bodies need nutrients for the immune system to work. • We need various minerals from our food to regulate various functions. • It is an enjoyable activity.

Inorganic and organic food

Organic food is made by living organisms, mostly plants and always have the element carbon in its structure. All life is carbon based.

Inorganic food is found naturally on Earth and with the exception of carbon dioxide and carbon monoxide, do not contain the element carbon.

Carbohydrates, Proteins, Lipids (fats and oils), Fibre and Vitamins.

Water and Mineral salts

Meat, eggs, fish, nuts

form part of our cell membranes and are responsible for many of their functions, all the microtubules in our cells that make our muscles contract, and our hair and nails. It can be used for energy and many vitamins, antibodies, essential for our immune system and all enzymes are protein.

Butter , cooking oil, cream

• form the main part of our cell membranes • protect many organs • all the steroid hormones are fats • fat soluble vitamins cannot be absorbed unless there is fat • vitamin D is made from fats • humans store their excess energy as fats, it is a very good source of energy

Bread, potatoes, cereals, wheat, maize

In plants carbohydrates form part of the structure of plants (cell wall) and is the main form of energy storage. Starch is not stored in animal bodies, but is the quickest form of food to burn as energy.

Water

• To keep our bodies cool (perspiration) • all chemical reactions take place in water • we need mineral salts to dissolve in our body before we can use them • the blood needs water to be able transport nutrients, oxygen, carbon dioxide etc

Vegetables, fruit, cereal

• it is indigestible thus it provides something for the walls of the gut to contract against once all the nutrients have been absorbed (peristalsis) • it slows down the absorption of glucose into the bloodstream • provides nutrition for the good gut bacteria • prevents constipation when taken with enough water • cleans out colon and helps prevent colon cancer

Vegetables, fruit, cereal

To produce mucous membranes thus preventing allergies, sunburn and blindness

Fat-soluble vitamin

Essential for our immune system and helps to keep our skin supple by keeping collagen intact

A water soluble vitamin

A complex of vitamins that helps maintain our metabolism and essential for nervous function

A water soluble vitamin

A fat soluble vitamin can be stored for longer periods of time in our bodies unlike water soluble vitamins which need to be replenished often