List two man-made ecosystems. [All India]
Garden and Pond are man-made ecosystems.
Describe how decomposers facilitate recycling of matter in order to maintain balance in the ecosystem. [Foreign]
Write one or two words for each of the following statements/definitions :Write one or two words for each of the following statements/definitions :
(a) Each level of food chain where transfer of energy takes place
(b) The physical factors like temperature, rainfall, light, soil, air and water of an ecosystem
(c) Organisms which depend on the producers for food either directly or indirectly
(d) The physical and biological world where we live in
(e) Selfcontained unit of living things and their non-living environment needing only sunlight for its functioning
Fill in the following blanks with suitable words :Fill in the following blanks with suitable words :
(a) Ultraviolet rays can cause skin…………………
(b) Pesticides enter the food chain at the…………………. level
(c) Grass →…………….→Human
(d) Lettuce →…………….→ Fox
(e) Plants→ Antelope→ …………….
Name the wastes which are generated in your house daily. What measures would you take for their disposal?
Which one of the following is not a terrestial ecosystem ?
Forest, Grassland, Aquarium, Desert
“Damage to the ozone layer is a cause for concern.” Justify this statement. Suggest any two steps to limit this damage. ‘ [Delhi]
Consider the food chain :
Grass → Deer → Lion
What will happen if all the lions are removed from the above food chain ?
‘If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind’. Justify this statement.
State two problems caused by the non- biodegradable waste that we generate in our daily life. [All India (C)]
Can the organisms of any trophic level be removed without causing any damage to the ecosystem ? Will the impact of removing all the organisms in a trophic level be different for different trophic levels ?
(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
Why did United Nations act to control the production of chlorofluorocarbons (CFCs) used in refrigerators? [Delhi]
State whether the following statements are true or false :State whether the following statements are true or false :
(a) In biology, human beings are called producers.
(b) Secondary consumers and tertiary consumers, both are carnivores.
(a) Define decomposers. Name one decomposer.
(b) What is the role of decomposers in the ecosystem ?
(a) With the help of a flow diagram, describe how energy from the sun flows through various trophic levels.
(b) Explain why, the flow of energy in the ecosystem is said to be unidirectional.
Give an example to illustrate that indiscriminate use of pesticides may result-in the degradation of the environment. [All India]
Which organisms belong to third and fourth trophic levels in the food chain comprising the following ?
Rats, Plants, Hawk, Snakes
How does a biodegradable waste differ from a non-biodegradable waste ? Give two examples of non- biodegradable wastes which pollute our environment.
Which of the following are biodegradable and which non-biodegradable ?
Glass bottle, Paper, Ball point pen refill, Hay, DDT, Wheat, Cake, Wood,
Polythene bag, Jute bag, Cotton cloth, Grass, Vegetable peels
(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 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 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.
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 ?