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प्रश्न
Explain why, the flow of energy in the ecosystem is said to be unidirectional.
Give scientific reasons:
In an ecosystem, the energy flow is always unidirectional.
उत्तर
Energy enters plants from the sun during food production through photosynthesis. This energy is then passed on from one organism to another in a food chain. The energy given out by organisms as heat is lost in the environment and does not return to be used by plants again. This makes the flow of energy in an ecosystem unidirectional. Thus, the flow of energy in an ecosystem is said to be unidirectional because the energy lost as heat from the organisms in a food chain cannot be reused by plants in photosynthesis.
संबंधित प्रश्न
List two biotic components of a biosphere.
List two important roles play in the environment by decomposers.
The following statement is true or false :
In biology, human beings are called producers.
Name one decomposer.
What is the role of decomposers in the ecosystem?
At which trophic level a person is feeding when he is eating bread.
At which trophic level a person is feeding when he is eating eggs.
Write one or two word for the following statement/definition :
Organisms which depend on the producers for food either directly or indirectly
What is a 'food web'? Show its formation.
Which of the following are decomposers of dead organisms?
| Bacteria | Fungi | Viruses |
| (a) no | yes | yes |
| (b) yes | no | yes |
| (c) yes | yes | no |
| (d) yes | yes | yes |
If a grasshopper is eaten by a frog, then the energy transfer will be from ______.
The sea water contains water beetles, tadpole, fish and weeds.
Which organisms are (i) predators, and (ii) prey?
A food chain occurring in the sea which provides food for many people can be written as :
phytoplankton → zooplankton → X → Y
Name one phytoplankton.
'If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind'. Justify this statement.
Explain why, a food chain usually cannot have more than three or four steps.
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.
What would happen if an organism is removed from the food chain?
The process of accumulation of harmful chemical substances like pesticides, in the body of living organisms at each trophic level of a food chain is known as ______.
Observe the food web and answer the questions given below:
Why do all food chains start with plants?
Natural agents like ______ are the decomposition factors breaking complex forms into simpler units.
