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प्रश्न
"Our food grains such as wheat and rice, the vegetables and fruits and even meat are found to contain varying amounts of pesticide residues." State the reason to explain how and why it happens?
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उत्तर
A large number of pesticides and chemicals are used to protect our crops from pests and diseases. Some of these chemicals are washed down into the soil, while some enter in the water bodies. From the soil, they are absorbed by plants along with water and minerals; and from water bodies, they are taken up by aquatic plants and animals. This is how these chemicals enter the food chain. Because these chemicals cannot decompose, they accumulate progressively at each trophic level. As the food chain proceeds, the concentration of pesticides also increases. This increase in the concentration of harmful chemicals with each step of the food chain is called biomagnification. That is why food grains, such as wheat and rice, vegetables, fruits and even meat are found to contain pesticide residue.
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संबंधित प्रश्न
Why are green plants called producers?
Which of the following belong to the same trophic level?
Tree ; Frog ; Snake ; Grass ; Lizard
What is a trophic level?
Organisms of a higher trophic level which feed on several types of organisms belonging to a number of lower trophic levels constitute the ______.
Some hunters are roaming in the plush green forest of Africa. They spot a deer and kill it. They decide to roast the deer there and then and eat it. When the hunters had just finished enjoying the feast of roasted deer, a lion attacks them. The lion kills one of the hunters and eats his flesh.
(a) write a food chain which provides food to lion in this case.
(b) Which animal (other than deer) the lion could look for food if he did not get the hunter as prey?
(c) Which other animal in the forest could have been in place of lion?
(d) How does the above food chain differ form the food chain such as : plants → goat → man?
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.
(a) In which organisms the pesticides enter from the polluted water? What is this level of organisms known as?
Arrange the following in a correct sequence and form a food chain
Human → Insect → Algae → Fish
In a given food chain if the amount of energy at the fourth trophic level is 6 kJ, what will be the energy available at the producer level?
Which of the following is an autotroph?
Natural agents like ______ are the decomposition factors breaking complex forms into simpler units.
