List three problems which arise due to the construction of big dams. Suggest a solution for these problems.
The construction of big dams poses the following problems:
(i) Social problems as the construction displace a large number of peasants and tribals without adequate compensation or rehabilitation.
(ii) They create economic problems as they use up huge amounts of public money without the generation of proportionate benefits.
(iii) Environmental problems because they contribute enormously to deforestation and the loss of biological diversity.
What is sustainable management? Why is reuse considered better in comparison to recycle ?
Energy flow in a food chain is unidirectional. Justify this statement. Explain how the pesticides enter a food chain and subsequently get into our body.
State the meaning of inherited traits and acquired traits. Which of the two is not passed on to the next generation? Explain with the help of an example.
List any four disadvantages of using fossil fuels for the production of energy.
