Grade 3 Science (NSO) : Food part 3 – Preservation of food

Food Decay and Preservation

Bacteria and fungi are the main groups of  decomposer organisms. Food decay is also known as food spoilage.

Bacteria and fungi need Food , Warmth and Moisture to grow.

There are several ways to stop or slow down the decay of foods. This is known as Food Preservation.

 

Food preservation methods

 Freezing

Bacteria cannot reproduce at low temperatures.

Bacteria and fungi need warmth to grow. In low temperatures they stop growing.

Following is the list of food preserved by freezing;

  • Meat
  • Fish
  • Fruits
  • Vegetables
  • Fresh foods
  • Cooked foods

Drying

Removing water prevents the microorganisms from growing, or digesting the food.

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Grade 3 Science (NSO) : Earth and universe

A quick look at the Grade 1 lessons :

Weather and The Sky:GK questions on space

Weather and The Sky: Earth and Sky fundamentals

 Solar system

Sun :

  • It is a star.
  • It gives us heat and light
  • It is the main source of energy on the earth
  • Eight planets and many heavenly bodies revolve around the sun.

Planets :

  • Orbits the sun
  • Has sufficient mass to be round, or nearly round
  • Is not a satellite (moon) of another object

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Grade 3 Science (NSO) : Animals

A look at the grade 2 lessons :

Animals:Lifecycle

Animals:Animal homes

Grade 2 science (NSO) : Animals

Animals:Baby names

Animals:Domestic and Wild

Animals: Classification

Animals:Facts about animals

Animals and the way they eat

Herbivores : Animals like cows , buffaloes , sheep etc., that eat plants.
Carnivores : Animals like lions, tigers, etc., that prey on and eat other animals.
Omnivores : Animals like bears, crows etc., that eat both plants and animals.
Scavengers : Animals like vultures and jackals that eat dead and left over animals generally preyed on by carnivores.

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