Biology · Environmental Studies

Ecosystem Nutrition and Energy Flow

1,235 Questions

Ecosystem nutrition and energy flow questions cover trophic levels, food chains, and biodegradable materials. These concepts frequently appear in general science sections of major competitive exams. Review these questions to build a solid understanding of ecological interactions.

Trophic levels conceptFood chain orderAutotrophic nutritionEnergy assimilationScavengers and decomposers

Ecosystem Nutrition and Energy Flow Questions

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Efficiency of energy transfer from one trophic level to the higher trophic level is called

  1. Assimilation efficiency

  2. Exploitation efficiency

  3. Lindeman's trophic efficiency rule

  4. Gross primary productivity
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Lindeman's trophic efficiency rule was introduced by Reymond Lindeman. According to this rule, the 10% of transfer of energy is transferred from one trophic level to the next successive trophic level. The rest of the energy is lost during transfer of energy and during respiration. The first trophic level has the maximum energy. 

Thus, the correct answer is 'Lindeman's trophic efficiency rule.'

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

The amount of usable energy remains constant as it is passed from one trophic level to another.

  1. True

  2. False

  3. Either

  4. Neither
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Organisms depend on the organisms of lower trophic levels for their energy requirements. There is a certain mass of living matter present in a trophic level at a particular time which is called standing crop and measured as mass of living organisms i.e. biomass. The biomass of species is measured in terms of dry weight. Transfer of energy from one trophic level to next trophic level follows 10 percent law known as Lindeman's law of trophic efficiency which states that the efficiency of energy transferred from one trophic level to the next higher trophic level is about 10%. So the energy decreases as it is transferred to subsequent trophic levels.
Hence, the statement given in the question is incorrect.
So, the correct answer is 'False'.
Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

The maximum energy is stored at following trophical level in any ecosystem

  1. Producers

  2. Herbivores

  3. Carnivores

  4. Top carnivores
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Producers are the green plants which synthesise their own food using sunlight.
B. Herbivores are primary consumers which feed on producers.
C. Carnivores are secondary consumers who feed primary consumers.
D. Top carnivores are tertiary consumers who feed on other carnivores.
Maximum energy is stored in the trophic levels of producers as they synthesise their own food. They occupy the lowest trophic level and energy is transferred from them to higher subsequent trophic levels. As the energy decreases each time it is transferred to the next higher trophic level, the lowest trophic level i.e. producers, have maximum energy.
So, the correct answer is 'Producers'.  
Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Grass $\rightarrow$ Deer $\rightarrow$ Tiger
In this food chain, the biomass of grass is $1$ tonne. The tiger biomass will be:

  1. $100 \,kg$
  2. $10 \,kg$
  3. $1 \,kg$
  4. $1000 \,kg$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

According to 10% law of Lindemann, if 1 tonne (1000 kg) biomass is present in grass, only 10% of it means 100 kg will go into deer and in tiger the biomass will be only 10 kg, i.e. 10% of deer's biomass.

So, the correct option is '10kg'.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Which of the cycle is concerned with energy flow in the ecosystem?

  1. Food cycle
  2. O$ _2$ cycle
  3. Cl$ _2$ cycle

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A food cycle is associated with energy flow in the ecosystem. It contains several trophic levels which are interdependent to each other for energy. Only 10% of energy can be transferred to the successive trophic level and rest 90% get utilise in their life processes.

Thus, the correct answer is option A.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

The transfer of energy from a level to another is governed by Law of thermodynamics. The average efficiency of energy transfer from herbivores to carnivores level is

  1. 10%

  2. 25%

  3. 5%

  4. 50%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The number of trophic levels in the grazing food chain is restricted as the transfer of energy follows 10 per cent law only 10 per cent of the energy is transferred to each trophic level from the lower trophic level.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Percentage energy transferred to higher trophic level in food chain is 

  1. 1%

  2. 10%

  3. 90%

  4. 100%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The ten percent law for the transfer of energy from one trophic level to the next was introduced by Raymond Lindeman (1942). According to this law, during the transfer of energy from organic food from one trophic level to the next, only about ten percent of the energy from organic matter is stored as flesh. The remaining is lost during transfer, broken down in respiration, or lost to incomplete digestion by higher trophic levels.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

About how much of the net primary productivity of a terrestrial ecosystem is eaten and digested by herbivores?

  1. 10%

  2. 1%

  3. 30%

  4. 50%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

According to the 10%  law, in a terrestrial ecosystem during the transfer of energy from one trophic level to the next, about ten percent of the energy in the form of organic matter is eaten and digested and stored as flesh. The remaining is lost during transfer in the form respiration or incomplete digestion. Thus the correct answer is option A.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Which of the following is the correct order of flow of energy?

  1. Plants--> tigers--> microbes--> goats

  2. Plants--> goats--> tigers--> microbes

  3. Tiger--> plants--> microbes--> goats

  4. Microbes--> tigers--> goats--> plants
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The flow of energy is always unidirectional. The energy passes from primary producers to primary consumers. From the primary consumers, the energy is passed to secondary consumers and then to tertiary consumers. Thus the energy pyramid is always upright.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

If first trophic level represent 100,000 kcal of energy. According to Lindman's law, how much energy is available to the fourth trophic level?

  1. 10 kcal

  2. 100 kcal

  3. 1,000 kcal

  4. 10,000 kcal

  5. 100,000 kcal
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
If first trophic level represents 100,000 kcal of energy, in second level it will have 10% of 100000 = 10000 kcal.
In third level, 10 % of 10000 = 1000 kcal
In fourth level, 10% of 1000 = 100 kcal
The Ten percent law is the transfer of energy from one trophic level to the next was introduced by Raymond Lindeman (1942). According to this law, during the transfer of energy from organic food from one trophic level to the next, only about ten percent of the energy from organic matter is stored as flesh.
Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Autotrophic species produce 400,000 kJ of energy in a tropical food web. The amount of energy at the level of secondary consumers is

  1. 40 KJ

  2. 400 KJ

  3. 4000 KJ

  4. 40, 000 KJ

  5. 4000, 000 KJ
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Energy transfer along each trophic level of a food chain exhibit loss of 90% energy as heat and transfer of only 10% energy to the next trophic level. The energy is lost in metabolic activities. According to this, out of 400,000kJ energy of primary producers, 40000kJ will be transferred to primary consumers and 4000kJ will be transferred to the secondary consumer. Tertiary consumers will obtain only 400kJ energy from secondary consumers while top consumers will obtain as little as 40kJ energy. Correct answer is option C.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows
Read the passage and answer the following question.

Assume you had a 10m$^2$ pond to study. You measured the amount of light energy bathing the water surface at 1,000kcal.


Based on the energy captured, about what percentage of that would be transferred to higher trophic levels?

  1. 1.65 percent

  2. 16.5 percent

  3. 33 percent

  4. 3.3 percent

  5. 66 percent
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ecological efficiency, or the percentage of energy transferred between trophic levels, is typically around 10 percent to 20 percent. 16.5 percent is a plausible value within this range.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

According to Lindeman's 10% law, only 10% energy is transferred to the next trophic level. If the plants produce 100 units of energy, the amount of energy at the level of secondary consumers would be

  1. 1 unit

  2. 25 units

  3. 50 units

  4. 70 units

  5. 80 units
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

10 percent Law introduced by Lindeman states that only 10% of energy is transferred from one trophic level to another and 90% of the energy is lost during transfer, respiration and digestion processes. Therefore if plants (present at producers level) produces 100 units of energy, 10% of it will be transferred to primary consumers (10 units of energy) and 10% of the subsequent energy is transferred to secondary consumers (1 unit of energy). Hence, the correct answer is option A.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Only a small portion of chemical energy in an apple is transferred to an organism that eats it.
What happens to the majority of the chemical energy stored in the apple when another organism eats it?

  1. The majority of the energy is spontaneously lost to the surroundings.

  2. The majority of the energy is used to do some kind of cellular work in the apple.

  3. The majority of the energy is lost as heat energy to the surrounding environment.

  4. The majority of the energy is destroyed or recycled.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The transfer of energy from one trophic level to another follows the 10% law of energy transfer. So, of the total energy created only 10% is passed on from the producers to the consumers while rest is used by the producer to carry out its activities

So, the correct answer is 'The majority of the energy is used to do some kind of cellular work in the apple'

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

The movement of energy and nutrients through living systems differs in what way? 

  1. Energy recycles while nutrients flow in two directions.

  2. Nutrients recycle while energy flows in one direction.

  3. Nutrients are lost as heat while energy forms chemical compounds.

  4. Nutrients are constantly available while energy is limited.

  5. Nutrients are lost as heat while energy is limited.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Energy is passed from one trophic level to the next trophic level. Hence energy flows in one direction through successive trophic levels in a food chain. Nutrients are produced from the matter. The matter may be organic or inorganic. The organic and inorganic matter is produced, exchanged and moved within the ecosystem and this is called cycling. Hence nutrients are recycled.
So, the correct answer is 'Nutrients recycle while energy flows in one direction'.