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A Test on Rachel Carson's Book Silent Spring

Decent Essays

AP Biology/Pd. 2
11/13/13
“Silent Springs” Test
Content Questions:
1. Carlson classifies modern insecticides into two groups of chemicals. The first group, represented by DDT, is known as the “chlorinated hydrocarbons” and the other group, represented by Malathion and parathion, consists of the organic phosphorus insecticides. Although both are organic, the organic phosphorous insecticides are more poisonous than the chlorinated hydrocarbons and have the ability to destroy enzymes.
2. When insecticides “are built on a basis of carbon atoms,” it is both ingenious and threatening because carbon atoms are the basic building blocks of the living world. They can be modified to become the chemistry of all life, but they can also be …show more content…

Too much of the insecticides will allow acetylcholine to build up which would lead to convulsions and eventually death.
2. Research in the early 1960s proved that high levels of DDT found in predatory birds were the cause of the decrease in their populations. When the predatory birds came in contact with DDT, their reproduction was directly affected. As a result of DDT's presence in the predatory bird's body, the eggshells of these birds started to become slender. These eggshells become so thin that whenever the mother bird would lie on the egg waiting for it to hatch, the eggs would break. Thus, the predatory bird population had no means of increasing, since their reproduction was not successful. Biological magnification had a large role to play in the decrease of the predatory bird population. Spraying of DDT on vegetation led to contamination of the prey populations such as fish. These prey started building large concentrations of DDT within their bodies. As a result, the predatory birds also got contaminated, since they preyed upon contaminated animals.
3. With regards to the genetic makeup of target insect populations, heavy pesticide use can alter their DNA to the point where the insects develop a resistance to certain insecticides like malaria mosquitoes to DDT. These effects can be counterproductive to long-term insect control because one the

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