Advertisements
Advertisements
Question
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
Advertisements
Solution
5,000 kJ
According to the 10 per cent law, only 10 per cent of the energy available in a trophic level is passed on to the next level. Hence, if the amount of energy available at the fourth trophic level is 5 kJ, the energy available at the producer level will be 5,000 kJ: 5 → 50 → 500 → 5,000.
APPEARS IN
RELATED QUESTIONS
Which of the following constitute a food-chain?
What are planktons?
Construct a food chain comprising the following :
Snakes, Hawk, Rats, Plants
A food chain represents a unidirectional flow of X. What is X?
Write down a food chain with five links in it.
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?
Construct a long food chain.
Write a common food chain of a pond ecosystem having four links.
Which of the following is not a producer?
(a) grass
(b) zooplankton
(c) phytoplankton
(d) paddy
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?
Match the terms given in column I with the terms given in column II and column III having the same meaning :
| Column I | Column II | Column III |
| (1) Secondary consumer | Herbivore | 1st trophic level |
| (2) Primary consume | Autotroph | 3rd trophic level |
| (3) Producer | Carnivore | 4th trophic level |
| (4) Tertiary consumer | Large carnivore | 2nd trophic level |
An aquatic food chain comprises of the organisms like tadpoles, weeds, fish and water beetles. The organism which gets the minimum energy through this food chain is :
(a) water beetles
(b) tadpoles
(c) weeds
(d) fish
The ten per cent law is associated with
(a) transfer of energy from various trophic levels to decomposers in a food chain
(b) transfer of ATP energy into muscular energy
(c) transfer of chemical energy from one organism to another
(d) transfer of sun's energy to the organisms called producers.
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.
Which organism will have the maximum amount of pesticides accumulated through the food chain? What is this process known as?
"Energy flow in food chains is always unidirectional". Justify this statement. Explain how the pesticides enter a food chain and subsequently get into our body.
Give one example of a food chain in an aquatic ecosystem?
Write the importance of the food chain.
Food chains are very important for the survival of most species.

Matter and energy are two fundamental inputs of an ecosystem. Movement of:
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
