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Question
'If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind'. Justify this statement.
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Solution
Chemical substances such as pesticides are sprayed over crop plants to protect them from pests and diseases. When herbivorous animals eat the plant food, these poisonous chemical pesticides go into their bodies. Man, being an omnivore, eats plant food as well as the meat of herbivores. Thus, the pesticides present in plant food and herbivores get transferred to man's body through food. Pesticides are non-biodegradable chemicals, so they get accumulated at each trophic level. Since humans occupy the top level in any food chain, the maximum amount of harmful chemical pesticides gets accumulated in our bodies, damaging our health gradually.
Hence the statement 'excessive use of pesticides to protect crops from diseases may cause long-term damage to mankind' is justified.
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- Why is the maximum concentration of pesticides found in human beings? (1)
- Give one method which could be applied to reduce our intake of pesticides through food to some extent. (1)
- Various steps in a food chain represent: (1)
- Food web
- Trophic level
- Ecosystem
- Biomagnification
- With regard to various food chains operating in an ecosystem, man is a: (1)
- Consumer
- Producer
- Producer and consumer
- Producer and decomposer
Arrange the following in a correct sequence and form a food chain
Human → Insect → Algae → Fish
Give some examples for Biodegradable and Non-biodegradable waste.
| S. No. | Biodegradable waste | Non-biodegradable waste |
| 1. | Food Waste | Plastic Bottles |
| 2. | ||
| 3. | ||
| 4. | ||
| 5. |
A food chain comprising birds, green plants, fish and man. The concentration of harmful chemical entering the food chain will be maximum in ______.
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