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) False.
(b) True.
Give a method for the disposal of household wastes such as left-over food, fruit and vegetable peels, and leaves of potted plants.
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 ?
What is the functional unit of the environment comprising of the living and non-living components called ?
(a) Define decomposers. Name one decomposer.
(b) What is the role of decomposers in the ecosystem ?
(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.
‘If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind’. Justify this statement.
In a food chain, 10,000 joules of energy is available to the producer. How much energy will be available to the secondary consumer to transfer it to the tertiary consumer? [All India ]
How does a biodegradable waste differ from a non-biodegradable waste ? Give two examples of non- biodegradable wastes which pollute our environment.
What name has been given to those organisms which break down the complex organic compounds present in dead animals and plants ?
Explain the terms ‘producer’ and ‘consumer’. Give two examples of producers and two of consumers.
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
What are the causes of depletion of ozone layer ? Which diseases are likely to be caused if the ozone layer will become thinner ?
(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.
Why is ozone layer getting depleted at the higher levels of the atmosphere? [Delhi (C)]
Which disease is caused in human beings due to depletion of ozone layer in the atmosphere? [Foreign]
Which one of the following is not a terrestial ecosystem ?
Forest, Grassland, Aquarium, Desert
How is ozone formed in the upper atmosphere? Why is the damage of ozone layer a cause of concern to us? State a cause of this damage. [Delhi(C)]
Describe how decomposers facilitate recycling of matter in order to maintain balance in the ecosystem. [Foreign]
Name the phenomenon in which non-biodegradable chemicals get accumulated progressively at each trophic level of a food chain.
Which of the following belong to the same trophic level ?
Goat; Spider ; Plants ; Hawk ; Rat .
Which of the following belong to the same trophic level ?
Tree ; Frog ; Snake ; Grass ; Lizard
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 ?