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Wednesday, 11 April 2012

GM Food

5.15 evaluate the potential for using genetically modified plants to improve food production (illustrated by plants with improved resistance to pests)

Genetically modifying plants can have some advantages and disadvantages. Despite the fact that the world produces enough food to feed the whole world many times over, some people are still starving. Others are suffering from malnutrition and many are hungry. Genetic modification has great potential; it can allow certain crops to survive in harsher conditions so that for example, people in Africa can grow crops despite the harsh conditions there. Scientists can even genetically modify foods so that they are more nutritious, for instance they genetically modified rice plants to produce 'Golden Rice' which has a higher vitamin A content. So here you see that GM foods can help address certain nutrient deficiencies too. Not all of a crop planted will be harvested; a percentage will be lost to disease, some to pests, others to weeds. So GM plants can be designed to have resistance to not only harsher conditions, but to pests too. This way crop yield is increased. But of course, there are disadvantages too. I'll just list a few of each, and then include a table for some benefits of genetic engineering applications to society.
Advantages, GM crops:
  • Need fewer chemical sprays
  • Could give bigger yields
  • Could grow in harsher conditions
  • Could result in cheaper food (if there were higher crop yields, supplies increase and with the same demand, prices are lowered)
  • Could be more nutritious
Adv. -Research into the genetic modification of plants hopes to provide (or provides already) plants with:
  • Increased resistance to a range of pests
  • Resistance to pathogens so they don't contract diseases
  • Increased heat and drought tolerance
  • Increased salt tolerance
  • A better balance of proteins, carbohydrates, lipids, vitamins and minerals-more nutritious crop plants
  • Accidental transfer of new genes to other wild plants-unpredictable
  • GM crops could reduce biodiversity
  • The new proteins in GM crops could cause allergies
  • GM seeds are expensive, but the costs of production are lower as sometimes less water is needed, or expensive chemicals such as herbicides and pesticides are not needed if the crops are resistant towards diseases and pests and weeds

Applications of genetic engineering
Benefits to society
Low-cost production of medicines
Genetic engineering of important drugs such as human insulin has dramatically reduced the cost of these medicines. This makes it more affordable and therefore more accessible to people who need them, so they can be treated.
Production of crops that grow in extreme conditions (e.g. high-salt environments)
Examples of such crops include:
  • Drough-resistant crops;
  • Salt-tolerant crops; and
  • Crops that make more efficient use of nitrogen and other nutrients.

This allows farmers to grow crops even when the soil conditions are not suitable for cultivating most crops.
Development of:
  • Crops that produce toxins that kill insect pests; and
  •  Pesticide-resistant crops

The use of costly pesticides that may damage the environment is reduced. For example, the Bt gene from t

1 comment:

  1. Olivia Cassidy1 May 2012 at 17:27

    Hi, just wanted to let you know that this post was very useful for my assignment. Thank you so much! All the way from Australia xx


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