A pesticide which is a chlorinated hydrocarbon is sprayed on a food crop. The food chain is: Food crop - Rat -Snake - Hawk. In this food chain, the highest concentration of the pesticide would accumulate in which one of the following?

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Q: 23 (IAS/2010)
A pesticide which is a chlorinated hydrocarbon is sprayed on a food crop. The food chain is: Food crop - Rat -Snake - Hawk. In this food chain, the highest concentration of the pesticide would accumulate in which one of the following?
Consider the following activities : 1. Spraying pesticides on a crop field. 2. Inspecting the craters of active volcanoes. 3. Collecting breath samples from spouting whales for DNA analysis. Q. At the present level of technology, which of the above activities can be successfully carried out by using drones ? (a) 1 and 2 only (b) 2 and 3 only (c) 1 and 3 only (d) 1, 2 and 3

question_subject: 

Science

question_exam: 

IAS

stats: 

0,153,62,37,16,9,153

keywords: 

{'pesticide': [0, 0, 1, 0], 'hydrocarbon': [1, 0, 2, 1], 'food chain': [4, 0, 1, 4], 'food crop': [2, 0, 0, 1], 'highest concentration': [0, 0, 1, 0], 'rat': [2, 1, 1, 0], 'snake': [0, 0, 0, 1], 'hawk': [1, 0, 2, 1]}

The highest concentration of the pesticide would accumulate in the hawk.

Chlorinated hydrocarbon pesticides such as DDT are persistent and tend to accumulate in the fatty tissues of organisms. This process is known as biomagnification, where the concentration of the pesticide increases as it moves up the food chain.

When a chlorinated hydrocarbon pesticide is sprayed on a food crop, it may be ingested by a rat that feeds on the crop. The pesticide may then accumulate in the fatty tissues of the rat. When a snake feeds on the rat, it ingests not only the pesticide present in the rat`s body but also the pesticide that has accumulated in its fatty tissues. Similarly, when a hawk feeds on the snake, it ingests not only the pesticide present in the snake`s body but also the pesticide that has accumulated in its fatty tissues. Thus, the highest concentration of the pesticide would accumulate in the hawk, which is at the top of the food chain.