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Our Environment-Important Questions & Preparation Tips

Jul 8, 2013 18:21 IST

    In this article you will get the clue that from where and how the questions are being framed from the chapter Our Environment

    The experts of jagranjosh.com have full confidence that you will not miss any of the questions in the board exam as well as in competitive exams from this chapter if you will keep the following terms / question in your mind while studying

    • Bio degradable waste and its uses
    • How harmful is DDT for our environment
    • Why some materials are biodegradable and some are not?
    • Ecosystem and its components
    • How does ecosystem function?
    • What are planktons?
    • What are decomposers and their importance for the environment?
    • What is ecosystem and what ate its components?
    • Difference Food chain food web
    • What are the various tropical levels in food chain?
    • How has man’s activities effected the ecosystem
    • What will happen if all the lion, deer and producers are removed?
    • Which of the following belong to same tropical level?

                            Grass, hawk, rabbit, frog,

    • Give example of a four step food chain operating in grassland. Name the secondary consumer in this food chain.
    • What is the difference between the food habits of organisms belonging to the first and the third tropic levels? Give one example each of the organisms belonging to these two tropic levels?
    • Can the organisms of any trophic level be removed without causing any damage to the ecosystem? Will the impact of removing all the organisms belonging to these two tropic levels?
    • Consider the food chain:


       What will happen if all the lions are removed from the above food chain?

    • The number of malaria patients in a village increased tremendously when large numbers of frogs were exported from the village. What could be the cause for it?
    • We do not clean ponds or lake but an aquarium needs to be cleaned periodically why?
    • How is energy transferred into food chain?
    • What do you understand by the statement that the flow of material in ecosystem is cyclic but flow of energy is unidirectional?
    • Explain the 10% law
    • Calculate the amount of energy available to lion in the following food chain if plant has 20000 J of energy available from the sun:


    • Consider the following food chain:


    • If in this chain, 100 J of energy is available at the producer level, then calculate the energy transferred to  the peacocks as food. State the law used in the calculation.
    • Which of the following will have the maximum concentration of harmful chemicals in its body? Peacock, frog, grass, snake, grasshopper.
    • What will happen if ozone layer gets depleted?
    • What are the different ways of managing the garbage we produce?
    • What is CFC? Mention the major resources of CFC. Give its harmful effects
    • What are the causes of depletion of ozone layer? Which diseases are likely to be caused if the ozone layer will become thinner?
    • If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind’ justify
    • What is mean by biological magnification? Explain with the help of food chain, how biological magnification of harmful chemical occur?
    • What is meant by bioconcentration of pesticides? Which common pesticides? Which common pesticide has accumulated human body in considerable amount?
    • Incineration and its use
    • Explain why the food chain consists of few steps only? Write a food chain having five steps

     Go through the some questions given here as example and get an idea that how questions can be framed

    Q.1 Edaphic factors are included in
                a. Abiotic components
                b.Biotic components
                c. Producers
                d. Consumers

    Q2. In the following groups of materials, which group (s) contains only non-biodegradable items?           

                     i.      Wood, paper, leather

                    ii.      Polythene, detergent, PVC

                    iii.      Plastic, detergent, grass

                    iv.      Plastic, bakelite, DDT

                                a. (iii)

                                 b. (iv)

                                c. (i) and (iii)

                                d. (ii) and (iv)

    Q3. Which of the following wastes cannot be decomposed by bacteria to form compost?

    1. Kitchen wastes 
    2. Plastic and polythene bags
    3. dead plants     
    4. bodies of insects living in the soil

    Q4. On an average, energy transferred from one trophic level to another is

    1. 5%
    2. 10%
    3. 15%
    4. 20%

    Q5.  In a lake polluted with pesticides, which one of the following will contain the maximum amount of pesticides?

    1. small fish
    2. microscopic animals
    3. big fish
    4. water birds

    Q6. Energv pyramids of an ecosystem lend to diminish at higher trophic levels. This is because   at each successive level

    1. energy is being lost from one level to the next.
    2. energy is being concentrated in fewer and larger organisms.
    3. the organisms become smaller.
    4. energy stored and passed is less.


    Q7. Assertion (A) :The Ozone layer in the atmosphere is getting depleted allowing more UV rays
    to reach earth. Reason (R) :CFC is broken down by UV radiation resulting attack on the Ozone molecules' damaging the Ozone umbrella of earth.

    1. Both 'A' and 'R' are true and 'R' is the correct explanation of A.
    2. Both 'A' and 'R' are true but 'R' is not the correct explanation of 'A'
    3. 'A' is false but 'R' is true.
    4. Both 'A" and R' are false

    Q8. The percentage of solar radiation absorbed by all the green plants for the process of photosynthesis is about

    1. 1%
    2. 5%
    3. 8%
    4. 10%

    Q9. Name the process in which a harmful chemical enters the food chain and gets concentrated at each level in the food chain.

    1. Concentration
    2. Biomagnifications
    3. Expansion
    4. Pollution

    Q10. Which of the following are environment-friendly practices ?

    1. Carrying cloth-bags to put purchases in while shopping.
    2. Switching off unnecessary lights and fans.
    3. Walking to school instead of getting your mother to drop you on her scooter.
    4. All of the above

    Q11. Air is composed of gases, water vapours and

    1. dust particles
    2. rainfall
    3. snowfall                                       
    4. light

    Q12. What will happen if deer is missing in the food chain given below ? Grass

    1. The population of tiger increases
    2. The population of grass decreases
    3. Tiger will start eating grass
    4. The population of tiger decreases and the population of grass increases

    Q13. Which of the following is non biodegradable?

    1. Tea leaves
    2. Nylon
    3. Remains of animals
    4. Fleece of sheep

    Q14. An ecosystem comprising of producers, herbivores and carnivores is an incomplete ecosystem if it does not include

    1. secondary consumers
    2. decomposers
    3. top carnivores
    4. secondary and tertiary consumers

    15.  Ultraviolet radiation from sunlight causes a reaction which produces

    1. Ozone   
    2. methane   
    3. Carbon dioxide 
    4. Chlorofluorocarbons

    Visit continuously in CBSE Section to Get SOLVED & UNSOLVED question papers, Sample papers, Practice papers, study material And Much More……

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