Strategies for Enhancement in Food Production Test - 12

Bacillus thuringiensis (or Bt) is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide. Many crystal-producing Bt strains, though, do not have insecticidal properties. The subspecies israelensis is commonly used for control of mosquitoes and of fungus gnats.

Pesticides are chemicals that are used to destroy pests and thus increase crop productivity. They are often persistent, induce resistance and ecological imbalance. Malathion is an organophosphate pesticide which affects the nervous system. It inhibits the action of acetylcholinesterase enzyme which leads to accumulation of acetylcholine at the synapse.

So, the correct answer is option B.

DDT (dichlorodiphenyltrichloroethane) is a colourless, crystalline, tasteless and almost odourless organochloride known for its insecticidal properties. It is a non-biodegradable, water-insoluble, chlorinated hydrocarbon once used worldwide as a major insecticide, especially in agriculture. In recent years, knowledge of its adverse impact on the environment has led to restrictions in its use. It is lipophilic, so, undergo bioconcentration when it enters into food chain. Milk is a carrier of DDT cause, DDT enters into food chain. Thus, the correct answer is option D.