Advertisements
Advertisements
Question
What will happen if we kill all the organisms in one trophic level?
Advertisements
Solution 1
If we kill all the organisms at one trophic level, it will create an imbalance in the ecosystem. For example, in a food chain, Grass → Deer → Lion, if we remove all lions, then the population of deer will increase, which will cause overgrazing. This will lead to deforestation. It may even lead to soil erosion, causing the further conversion of fertile land into barren deserts.
Solution 2
If we kill all the organisms in one trophic level, the transfer of food energy to the next trophic level will stop. This will cause a break in the food chain, resulting in an imbalance in the ecosystem. As a result, the organisms of the higher trophic level will also die, while the individuals of the lower trophic level will exhibit enormous growth in their population. Both conditions will result in an ecological upset.
APPEARS IN
RELATED QUESTIONS
In a food chain of frog, grass, insect and snake, assign trophic level to frog.
Why are green plants called producers?
We do not clean natural ponds or lakes but an aquarium needs to be cleaned regularly. Why is it so ? Explain.
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What is biological magnification?
Name the organisms belonging to the second and the fourth trophic levels in the food chain comprising the following :
Frogs, Plants, Snakes, Hawk, Insects
Fill in the following blank with suitable word :
Decomposer organisms are..........in their action.
In a food chain, the initial organism is usually :
(a) photosynthetic
(b) herbivore
(c) saprophytic
(d) parasitic
If a grasshopper is eaten by a frog, then the energy transfer will be from ______.
Which of the following statement is incorrect?
What would happen to the number of grass plants and foxes if the number of rabbits decreased?
Fill in the following blank with suitable word :
Lettuce → ............. → Fox
With the help of a food chain, explain how biological magnification of harmful chemicals can occur.
In addition to wheat plants, a crop field ecosystem has organisms such as snake, peacock, eagle and mice. If the wheat plants are sprayed with pesticides periodically, which of the following will have the minimum concentration of pesticides in the body?
(a) snake
(b) eagle
(c) mice
(d) peacock
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?
What would happen if an organism is removed from the food chain?
Observe the food web and answer the questions given below:
Why do all food chains start with plants?
In a food chain, the third trophic level is always occupied by
DDT was sprayed in a lake to regulate breeding of mosquitoes. How would it affect the trophic levels in the following food chain associated with a lake? Justify your answer.
Assertion (A): The energy which passes to the herbivores does not come back to autotrophs.
Reason (R): The flow of energy in a food chain is unidirectional.
