Our environment Worksheet-6

Our environment Worksheet-6


  1. Which of the following belong to the first trophic level:

(a) Grasshopper, Rose plant, Neem tree, Cockroach.

(b) Sunflower plant, Grasshopper, Cockroach, Banyan tree.

(c) Sunflower plant, Grasshopper, Rose plant, Cockroach?


  1. Which of the following belong to the second trophic level:

(a) Frog, Butterfly, Spider, Rice weevil?

(b) Parrot, Frog, Butterfly, Spider?


  1. State one difference between autotrophs and heterotrophs.


  1. Write a food chain in a forest ecosystem.


  1. What is meant by aerosol?


  1. What destructive effect do the chlorofluoro carbons bring about in the atmosphere?


  1. Name two materials which can be recycled.


  1. Name the chemicals that cause depletion of ozone layer.


  1. Name the disease which is likely to be caused if the ozone layer gets depleted.


  1. How does atmosphere protect the living beings from radiations?


  1. Which chemicals are responsible for the infiltration of ultraviolet rays to the earth?


  1. Name any two wastes that can be recycled and reused.


  1. Can non-biodegradable chemicals cause biomagnification? What is biomagnification?


  1. Name two main abiotic factors, which affect human environment.


  1. In the following food chain, plants provide 2000 J of energy to rats. How much energy will be available to hawks from snakes?

Plants → Rats → Snakes → Hawks


  1. During heavy rains in a village, the rain water carried excessive nitrogen compounds to a pond. How will it affect the growth of fish in the pond in the long run?


  1. In the food chain given below, grass provides 4000 J of energy to grasshopper. How much energy will be available to snakes from frogs :

Grass → Grasshopper → Frogs → Snakes?


  1. Which food habits give us more energy: Vegetarian or non-vegetarian?


  1. Indicate the energy flow through a simple food chain, with rabbit as one of its constituents.


  1. Name the organism that represents the first trophic level in any food chain.



  1. (a) Rose plant and neem tree,

(b) Sunflower plant and Banyan tree,

(c) Sunflower plant and rose plant.


  1. (a) Butterfly and Rice weevil, (b) Parrot and Butterfly.


  1. Autotrophs make their own food by the process of photosynthesis. Heterotrophs cannot make their own food and they depend upon autotrophs or other heterotrophs.


  1. Grass                → Deer                 → Lion

(producers)       (herbivore)        (carnivore)


  1. Aerosol is colloidal solution of solids in air.


  1. Chlorofluorocarbons cause depletion of ozone layer.


  1. Plastic and glass pieces.


  1. Chlorofluorocarbons.


  1. Skin cancer.


  1. In stratosphere, ozone layer protects us from UV radiations.


  1. Chlorofluorocarbons (CFCs).


  1. Plastic materials and wastes coming out of industries such as metals can be recycled and reused.


  1. Some non-biodegradable chemicals like DDT enter our food chain and get accumulated in the bodies of organisms with increase in amount and effect at each step. This is called biomagnification.


  1. Air and water.


  1. 20 J of energy


  1. Excess growth of algae leads to oxygen depletion in water resulting in the death of fishes.


  1. 40 J of energy.


  1. Vegetarian food chain gives us moiré energy as it is shorter than non-vegetarian chain.


  1. Plant → Rabbit → Hawk.


  1. Green plants.