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प्रश्न
What is a food chain?
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उत्तर
The sequence of living organisms in a community in which one organism consumes another organism to transfer food energy is called a food chain. An example of a simple food chain is that operating in a grassland.
संबंधित प्रश्न
The first trophic level in a food chain is always a green plant. Why ?
We do not clean natural ponds or lakes but an aquarium needs to be cleaned regularly. Why is it so ? Explain.
List two important roles play in the environment by decomposers.
Which of the following constitute a food-chain?
What is biological magnification?
What name has been given to those organisms which break down the complex organic compounds present in dead animals and plants?
Give an example of a four step food chain operating in grassland. Name the secondary consumer in this food chain
At which trophic level a person is feeding when he is eating bread.
Write one or two word for the following statement/definition :
Each level of food chain where transfer of energy takes place
What will happen if deer is missing in the food chain given below?
Grass → Deer → Tiger
In the figure given alongside, the various trophic levels are shown in the form of a pyramid. At which trophic level the maximum energy is available?
One of the following is a micro-consumer. This one is :
(a) ant
(b) lice
(c) fungi
(d) mosquito
The sea water contains water beetles, tadpole, fish and weeds.
Which organisms in the food chain are herbivore, and carnivores?
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 a harmful chemical enters a food chain comprising cat, mice and plants, which one of these organisms is likely to have the maximum concentration of the harmful chemical in its body?
The following statement is true or false :
Only 10 per cent of the light energy given by the sun is available for transfer at each higher trophic level in a food chain.
'If we excessively use pesticides to protect the crops from diseases, then it may cause long-term damage to mankind'. Justify this statement.
What is meant by bioconcentration of pesticides
Calculate the amount of energy that will be available to big fish in the following food chain, if 10,000 J of energy is available to small algae from the sun :
Small algae → Zooplankton → Fish → Big fish
In the food chain given below, if the amount of energy available at fourth trophic level is 5 kJ, what was the energy available at the producer level?
Grass → Grasshopper → Frog → Snake → Hawk
(a) 500 kJ
(b) 50 kJ
(c) 5000 kJ
(d) 5 kJ
A food chain comprises of cat, seed-eating bird, plants, and dog. The organism which will have the maximum concentration of harmful pesticides coming through the food chain is most likely to be :
(a) cat
(b) plants
(c) dog
(d) seed-eating bird
A food chain consists of fish, larvae, phytoplanktons and birds. The level of pesticides in water in which the fish, larvae and phytoplanktons live is quite high.
Write the food chain comprising all the organisms mentioned above.
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.
| Human body is made up of five important components, of which water is the main component. Food, as well as potable water, are essential for every human being. The food is obtained from plants through agriculture. Pesticides are being used extensively for a high yield in the fields. These pesticides are absorbed by the plants from the soil along with water and minerals and from the water bodies these pesticides are taken up by the aquatic animals and plants. As these chemicals are not biodegradables, they get accumulated progressively at each trophic level. The maximum concentration of these chemicals gets accumulated in our bodies and greatly affects the health of our mind and body. |
- Why is the maximum concentration of pesticides found in human beings? (1)
- Give one method which could be applied to reduce our intake of pesticides through food to some extent. (1)
- Various steps in a food chain represent: (1)
- Food web
- Trophic level
- Ecosystem
- Biomagnification
- With regard to various food chains operating in an ecosystem, man is a: (1)
- Consumer
- Producer
- Producer and consumer
- Producer and decomposer
Observe the food web and answer the questions given below:
Why do all food chains start with plants?
Differentiate between herbivores and carnivores.
In the given food chain, suppose the amount of energy at the fourth trophic level is 5 kJ, what will be the energy available at the producer level?
Grass → Grasshopper → Frog → Snake → Hawk
What will happen if deer is missing in the food chain given below?
Grass → Deer → Tiger
