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قديم 30-11-2009, 07:38 PM
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تاريخ التسجيل: Aug 2009
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افتراضي Should scientists modify our food

Should scientists modify our food?
Thousands of years ago, most people were hunters whose food came from the animals and fish they had killed and from nuts, roots and fruit they had collected. Later, these hunters lived in one place and became farmers whose method of getting food was to grow crops from the seeds of wild plants. Over time, they noticed that some plants were better than others. They saved the seeds from these plants and so the yields and quality of their crops improved.
Like plants, all other living things contain genes which control what they will be like. Modern scientists can put genes into plants and animals in their laboratories, and this means they can modify their genes in order to change what they are like. This is called genetic engineering.
A type of tomato is an example of this. When normal tomatoes ripen, one of their genes produces a chemical that makes the fruit rot. Scientists can modify this gene so that the tomatoes do not rot so quickly. This is one way in which genetically modified (GM) crops can improve agriculture. Scientists know that this technology can also protect people from starvation in countries where insects or diseases destroy crops. For example, fruit and vegetables have been modified so that they are not damaged by the diseases that kill ‘normal’ plants.
However, many people believe that modified food is unnatural and fear that genetic engineering may bring new diseases in the future. So should we eat genetically modified food or not? Surprisingly, biscuits, cakes and many other foods that we have been eating for years already contain genetically modified ingredients. Have they done us any damage?

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