What are the after effects of ozone depletion?
Ozone depletion will create holes in the stratosphere, which will allow the UV rays to enter the earth. The UV ray that reaches the skin can cause disastrous effect.
Name the phenomenon in which non-biodegradable chemicals get accumulated progressively at each trophic level of a food chain.
What is the functional unit of the environment comprising of the living and non-living components called ?
Which one of the following is not a terrestial ecosystem ?
Forest, Grassland, Aquarium, Desert
If a harmful chemical enters a food chain comprising cat, mice and plants, which one of these organisms is likely to have the maximum concentration of the harmful chemical in its body ?
Why is ozone layer getting depleted at the higher levels of the atmosphere? [Delhi (C)]
(a) Define decomposers. Name one decomposer.
(b) What is the role of decomposers in the ecosystem ?
The number of malaria patients in a village increased tremendously when large number of frogs were exported from the village. What could be the cause for it ?
Give a method for the disposal of household wastes such as left-over food, fruit and vegetable peels, and leaves of potted plants.
(a) Describe an activity to show that while paper is biodegradable but plastic (say, polythene) is non-
biodegradable.
(b) Explain why, some materials are biodegradable but some are non-biodegradable.
(a) What is meant by non-biodegradable waste materials ? Give two examples of non-biodegradable wastes.
(b) Which of the following materials are biodegradable ?Animal bones, Iron nails, Plastic mugs, Leather belts, Silver foil
(a) Define an ecosystem. Give examples of any two ecosystems.
(b) List the biotic and abiotic components of an ecosystem.
Explain how, harmful ultraviolet radiations of sunlight are prevented from reaching the earth’s surface.
‘If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind’. Justify this statement.
Why are bacteria and fungi called decomposers? List any two advantages of decomposers to the environment. [Delhi]
What happens when higher energy ultraviolet radiations act on the oxygen at the higher level of the atmosphere? [All India]
Which of the following belong to the same trophic level ?
Tree ; Frog ; Snake ; Grass ; Lizard
How does a biodegradable waste differ from a non-biodegradable waste ? Give two examples of non- biodegradable wastes which pollute our environment.
A student went to study a local pond. In one part of the pond she noticed tadpoles scraping at some pond weed. In another part she saw a water beetle holding a tadpole in its jaws.A student went to study a local pond. In one part of the pond she noticed tadpoles scraping at some pond weed. In another part she saw a water beetle holding a tadpole in its jaws.
(a) Construct a food chain for the pond.
(b) How many links are there in this chain ?
(a) What is meant by biodegradable waste materials ? Give two examples of biodegradable wastes.
(b) Which of the following materials are non-biodegradable ?
Aluminium wire, Tea leaves, Synthetic fibre, Wool