Name the wastes which are generated in your house daily. What measures would you take for their disposal?
The wastes generated daily are kitchen wastes, paper wastes like newspapers, bags, envelopes, plastic bags, vegetable and fruit peels, dust and empty cartons, etc. Measures for disposal are:
(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 decomposers. Name one decomposer.
(b) What is the role of decomposers in the ecosystem ?
‘If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind’. Justify this statement.
Give an example to illustrate that indiscriminate use of pesticides may result-in the degradation of the environment. [All India]
Name the process in which a harmful chemical enters the food chain and gets concentrated at each trophic level.
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 ?
Select two non-biodegradable substances from the following waste generated in a kitchen: spoilt food, paper bags, milk bags, vegetable peels, tin cans, used tea leaves. [Delhi]
Which of the following belong to the same trophic level ?
Tree ; Frog ; Snake ; Grass ; Lizard
Which one term in the following includes the others ?
air, flora, fauna, environment, water, sunlight, soil
Explain how, harmful ultraviolet radiations of sunlight are prevented from reaching the earth’s surface.
Give a method for the disposal of household wastes such as left-over food, fruit and vegetable peels, and leaves of potted plants.
Which disease is caused in human beings due to depletion of ozone layer in the atmosphere? [Foreign]
Why did United Nations act to control the production of chlorofluorocarbons (CFCs) used in refrigerators? [Delhi]
Which of the following belong to the first trophic level of a food chain? Grass, Grasshopper, Plants, Rat, Tiger [Foreign]
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.
Which organisms belong to third and fourth trophic levels in the food chain comprising the following ?
Rats, Plants, Hawk, Snakes
Fill in the following blanks with suitable words : Fill in the following blanks with suitable words :
(a) Decomposer organisms are……………. in their action.
(b) In nature, all green plants are……………. whereas animals are consumers.
(c) A series of organisms, each of which feeds on the next organism, the beginning of which is a green plant, is called a…………….
(d) The science that deals with the inter-relationships of living things with one another and their environment is called …………….
(e) Plastic is a……………. material whereas paper is a……………. material.
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 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) Define an ecosystem. Give examples of any two ecosystems.
(b) List the biotic and abiotic components of an ecosystem.
If 5 joules of energy is available at producer level (plants), then how much energy will be transferred to the lion in the following food chain ? If 5 joules of energy is available at producer level (plants), then how much energy will be transferred to the lion in the following food chain ?
Plants —> Goat —> Lion