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

Energy transfer from one trophic level to another is

  1. 10%

  2. 5%

  3. 15%

  4. 20%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat. The efficiency with which energy or biomass is transferred from one trophic level to the next is called as the ecological efficiency. Consumers at each level convert on average only about 10% of the chemical energy in their food to their own organic tissue (the ten-percent law). 

Therefore, the correct answer is option A.

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

Flow of energy declines as it passes from lower to higher trophic level. This is explained by

  1. First law of thermodynamics

  2. Second law of thermodynamics

  3. Newtons second law

  4. Newtons third law
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Flow of energy declines as it passes from lower to higher trophic level. This is explained by second law of thermodynamics. According to this law, the energy decreases from one trophic level to the next trophic level because energy is lost as metabolic heat during transfer of energy. When food energy passes from producers to herbivores to carnivores, only 10% of energy is transferred from one trophic level to another trophic level.

Thus, the correct answer is 'Second law of thermodynamics.'

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

Consider the components of a food chain producers $ \rightarrow\ $ herbivores $ \rightarrow\ $ carnivores $ \rightarrow\ $ top carnivores. Eventually what happens to all the energy passed from one element to the next?

  1. It recycles back to the producers

  2. It results in a much larger decomposer population

  3. It is dissipated into the environment.

  4. It is recaptured by another food chain
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A food chain can be described as a series of energy dilutors, the energy that fails to reach the next level being dissipated as heat or movement. Most of the energy contained in the food of animal consumers is used by them during the processes of food collection, digestion, and other essential metabolic activity.

So, the correct option is 'It is dissipated into the environment.'

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

The only requirement of an ecosystem is a constant input of energy that comes by the process of respiration

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. 
  • Energy flow is the amount of energy that moves through a food chain. 
  • Energy that is not used in an ecosystem is eventually lost as heat. 
  • Energy is passed on from one trophic level to the next trophic level and each time some energy is lost as heat into the environment. 
  • This is due to the fact that each organism must use some energy that they received from other organisms in order to survive. 
  • The top consumer of a food chain will be the organism that receives the least amount of energy.
So the given statement is false.

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

Read the following statements carefully:
(I) Energy transfer in the biotic world always proceeds from the autotrophs.
(II) Energy flow in undirectional
(III) Energy availability is maximum at the tertiary level.
(IV) There is loss of energy from one trophic level to that other.
Select the relevant statements for the forest ecosystem.

  1. I, II and IV

  2. I, II and III

  3. I, III and IV

  4. II, III and IV
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A forest ecosystem is formed by the community of organisms which live in a forest. The relevant statement for the forest ecosystem are:
I→ Energy transfer in the biotic world always proceeds from the autotrophs as the plants and the trees are the major producers. 
II→ Energy flow is unidirectional.
IV→ There is a loss of energy from one trophic level to the other as the law of energy transfer is applicable to this ecosystem.
Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Four species of birds have different egg colours: [1] white with no markings, [2] pale brown with no markings, [3] grey-brown with dark streaks and spots, [4] pale blue with dark blue-green spots. Based on egg colour, which species is most likely to nest in a deep tree hole?

  1. 1

  2. 2

  3. 3

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

White birds with no markings would likely to nest in a deep tree hole as they can't camouflage with the surroundings and can easily be prey for its predators. Others can hide themselves under the color of trees. 

Therefore, the correct answer is option A.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Study statements (a - d) and select the two correct statements. 
(a) A lion eating a deer and a sparrow feeding on grain are consumers.

(b) Predator starfish and Pisaster help in maintaining species diversity of some invertebrates.
(c) Predators ultimately lead to the extinction of prey species.
(d) Plant chemicals like nicotine and strychnine are produced due to metabolic disorders. 

  1. c and d

  2. a and d

  3. a and b

  4. b and c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement (a) is correct as both are consumers. Statement (b) is correct as Pisaster is a well-known keystone predator that maintains diversity. Statement (c) is incorrect because predators rarely drive prey to extinction, and (d) is incorrect because these chemicals are secondary metabolites, not disorders.