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प्रश्न
What will be the amount of energy available to the organisms of the 2nd trophic level of a food chain if the energy available at the first trophic level is 10,000 joules?
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उत्तर
On applying the 10% law to the food chain, the organisms of the 2nd trophic level of the food chain will have 1000 joules of energy.
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संबंधित प्रश्न
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What will happen if we kill all the organisms in one trophic level?
Which organisms belong to third and fourth trophic levels in the food chain comprising the following?
Rats, Plants, Hawk, Snakes
A food chain represents a unidirectional flow of X. What is X?
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?
Which of the following represents a possible food chain found in a pond :
| Primary producers |
Primary consumers | Secondary consumers |
| (a) green algae | fish | mosquito larvae |
| (b) fish | green algae | mosquito larvae |
| (c) mosquito larvae | fish | green algae |
| (d) green algae | mosquito larvae | fish |
The sea water contains water beetles, tadpole, fish and weeds.
Which organisms are (i) predators, and (ii) prey?
With the help of a food chain, explain how biological magnification of harmful chemicals can occur.
The surface of water in a lake appears green due to a layer of tiny free-floating organisms X on its surface. The lake water also contains organisms like water beetle, fish and tadpole. The sun shines over the lake water and provides energy for the functioning of this lake ecosystem.
(a) What could organisms X be?
(b) Write a food chain comprising of all the four organisms mentioned.
(c) What is the general name of the food chains like the one written above?
(d) Name (i) secondary consumer (ii) producer (iii) tertiary consumer, and (iv) primary consumer, in the above food chain.
(e) If the tertiary consumer gets 0.2 J of energy from the secondary consumer, then how much energy was radiated by the sun to the producer?
Your mother always thought that fruit juices are very healthy for everyone. One day she read in the newspaper that some brands of fruit juices in the market have been found to contain certain level of pesticides in them. She got worried as pesticides are injurious to our health.
(a) How would you explain to your mother about fruit juices getting contaminated with pesticides?
(b) It is said that when these harmful pesticides enter our body as well as in the bodies of other organisms they get accumulated and beyond a limit cause harm and damage to our organs. Name the phenomenon and write about it.
