C3 Revision Cards

Revision cards for OCR's Science for the 21st Century C3 unit.

  • Created by: kanojyoxx
  • Created on: 17-06-10 10:46


  • Nitrogen cycle.
  • When plants are removed from the soil, the nitrogen in that part of the cycle is lost - it needs to be replaced.
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Organic and Intensive Farming Differences

  • Organic farms use natural predators, natural pesticides and crop rotation to rid themselves of pests - intensive farming uses chemicals.
  • Organic farms use animal waste, manure and crop rotation to help fertilise - intensive farming uses chemicals.
  • Organic farming is more expensive than intensive farming.
  • Organic produce is mroe expensive than intensive produce.
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Polymers and Digestion

  • Carbohydrates, made of Oxygen Hydrogen and Carbon, are found in potatoes, museli and bread. The polymers are starch and cellulose, and the monomer is glucose.
  • Proteins, made of Oxygen Hydrogen Carbon and Nitrogen, are found in meat eggs and fish. The monomers are amino acids.
  • Excess proteins are transported to the liver to be made into Urea, and then the urea is extracted in the kidneys and put out with urine.
  • Proteins are used mostly for tendons, but also hair, skin and muscles.
  • Digestion: food goes through oesophagus, stomach, small intestine, large intestine, poop.
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  • Type 1 is developed in younger people - the body cannot make any insulin. Treated by insulin injections.
  • Type 2, until recently, mostly developed in older people - the body either can't make enough insulin, or the body stops reacting to it properly. Treated by died, losing weight and exersice.
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Food Additives

  • Colourings - make food look more attractive, replace colours lost in transport.
  • Flavourings - make food smell and taste better.
  • Sweetners - make food sweeter so you don't have to use as much sugar and makes the food have less calories.
  • Antioxidants - stop foods containing fat going off when they react with oxygen - ie sausages.
  • Preservatives - make the food so that microbes can't grow on it and keeps the food fresher for longer.
  • Emulsifiers - join oil and water.
  • Stablilisers - keep oil and water joined.
  • Additives, other than flavourings, are governed by the EU. They are given and E Number if they pass a safety test.
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Safe and Healthy Food

  • Food can never be risk-free.
  • It could contain residues of chemicals from pesticides and herbicides.
  • It could have been contaminated during transport or storage.
  • It could be cooked dangerously - burned to form HA or PAHs which can cause liver cancer.
  • You should try to eat healthy- try not to eat food that could contain chemicals, instead eat organic food. Wash, store and cook food properly.
  • The labels contain information about calories, typse of fat, where the food was produced, and daily recommened amounts of the food.
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it is very useful



This was good :) very useful



thankyou, very useful! :) saved me typing up my own notes!:) 



is this c3 to you? kmttt

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