Bio Final: Pesticides & Organic Farming
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Created by:
brainville on May 6, 2009
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9 terms
Terms | Definitions |
|---|---|
 need for pesticides | farmers selected the varieties of their crops based upon productivity alone, they inadvertently eliminated the genetic variation that protected crops from natural pests. |
| potato famine of Ireland | caused by genetically uniform crops and lack of pesticides to protect them; a fungus developed and wiped out a large portion of the population |
| biomagnification | The concentration of pesticides in higher levels of food chains |
| organism's resistance to pesticide | Those "more tolerant" individuals were the only ones who could successfully survive and reproduce. After many generations of this occurring, the population becomes dominated by resistant forms and DDT was no longer as effective as it once was. |
| DDTs effect on the eagle | DDT originally absorbed by the plants on which it was sprayed --> into body tissues of the insects who consumed the plants --> Insectivores (fish) then absorbed the DDT when they ate insects and had a much higher concentration in their body tissues --> when eagles consumed the fish, they ended up with toxic levels of DDT in their body tissues. |
| Endangered Species Act of 1973 | The Secretary of the Interior is given the power to determine if a species is threatened or endangered. Once a species is designated as endangered, the Secretary can then develop plans to help the species recover. |
| endangered | Any species that is in danger of extinction throughout all or a significant portion of its range |
| organic | Foods produced without hormones, antibiotics, herbicides, insecticides, chemical fertilizers, genetic modification or germ-killing radiation |
| threatened | Any species that is likely to become an endangered species within the foreseeable future |
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