Biology · Environmental Studies

Ecosystem Nutrition and Energy Flow

1,093 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 evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Which of the following is false?

  1. Quantity of biomass in trophic level at a particular period is called as standing crop.

  2. The energy content in trophic level is determined by considering a few individuals of a species in that trophic level.

  3. The succession that occurs in newly cooled lava is called as primary succession.

  4. Rate of succession is faster in secondary succession.

  5. Phytoplanktons are the pioneers in the aquatic ecosystem.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Trophic level refers to each levels in the  ecological pyramid and is designated as per their position in the food chain. The trophic level starts from 1 -which represents the primary producers and it moves upto  primary consumers- level 2, secondary consumers -level 3 and tertiary consumers at level 4 or 5. In an aquatic ecosystem, the phytoplanktons are the pioneers and primary producers along with the algae and cyanobacteria. Standing crop refers to the mass of living material present at a trophic level at a particular time. The ecological succession takes place from primary to secondary and reaches a climax stage. primary succession refers to the ecological succession that takes place where no living organisms ever existed. for eg. the sucession that occurs in a newy cooled lava.  Moreover, it has been seen that the rate of succession is faster in secondary than the primary succession as soil is already present in case of secondary succession.

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

In a food chain, deer is eaten by lion and deer east vegetation. Which one of the statements given is true?
(P) Lion is second order consumer and deer is first order consumer.
(Q) Lion is predator and deer is prey.
(R) Lion is first order consumer and deer is second order consumer.
(S) Lion is third order consumer and deer is second order consumer.

  1. Only (P) and (Q)

  2. Only (Q) and (R)

  3. Only (P) and (S)

  4. Only (P) and (R)

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

In a food chain where a deer feeds on producers and lion feeds on the deer then, the deer is a first order consumer and the lion is a second order consumer, and as the lion feeds in the deer, lion is the predator and the deer is the prey. 

Thus, the correct answer is option A. 

Multiple choice evs - i insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

If a grassland food chain is linked to the food chain in the forest. It can be termed as

  1. Ecosystem

  2. Food chain

  3. Food web

  4. None of the above

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When different food chains from different ecosystems (like grassland and forest) interact or overlap, the resulting complex network is described as a food web.

Multiple choice evs - i insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Which of the following statement defines the difference between the food chain and food web?

  1. Food chain demonstrates the interdependence.

  2. Food web demonstrates the interlinked food chain.

  3. Food chain is an exchange of energy.

  4. None of the above

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A food chain is a single linear path of energy flow, whereas a food web is a collection of many interlinked food chains that better represent the complexity of an ecosystem.

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

A peacock eats snakes which eat frogs. These eat hoppers which in turn thrive on leaves of the plants. The peacock is

  1. Primary consumer

  2. Secondary consumer

  3. Decomposer

  4. Apex of the food pyramid

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Apex of the food pyramid is the tip of the food pyramid. In the given food pyramid, peacock eats snakes which eat hoppers which in turn eats leaves of the plants. Hence, the peacock is the apex of food pyramid and plants are the base of the food pyramid.  Hoppers are primary consumer and snakes are secondary consumers of the given food pyramid.

Thus, the correct answer is 'Apex of the food pyramid.'

Multiple choice evs - i insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Extinction of a species in a food chain is compensated in

  1. Ecological pyramid

  2. Food web

  3. Food chain

  4. None of the above

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Food web is interconnected food chains in an ecosystem. Extinction of a species in a food chain is compensated in food web. When a particular species in a food chain becomes extinct, it is compensated by the remaining generalized species at the same trophic level.

Thus, the correct answer is 'Food web.'

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Which of the following statements about food chains are correct?
(a) Removal of 80% tigers resulted in increased growth of vegetation.
(b) Removal of most carnivores resulted in an increased population of deer.
(c) Length of the food chain is limited to 3-4 trophic levels due to energy loss.
(d) Length of the food chain may vary from 2-3 trophic levels.

  1. a, d

  2. a, b

  3. b, c

  4. c, d

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In a food chain, the carnivores eat up herbivores, or in other words, the secondary consumers consume the primary consumers. So, we can say that if the number of carnivores decreases, the number of herbivores like deer go on decreasing as they will not get eaten up. So, removal of most of the carnivores will result in an increased population of deer. 

Apart from this, we also know that as we move from one tropic level to another, the amount of energy goes on decreasing. This is according to the 10% law according to which, at each trophic level, 10& energy is lost. So, each food chain is only 3-4 tropic levels long due to these energy losses. 
So, option b and c is the correct option.
So the correct option is C.

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Which of the following occupies more than one trophic level in the same ecosystem at the same time?

  1. Sparrow

  2. Goat

  3. Frog

  4. Lion

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

In an ecosystem, there are various trophic levels. Each trophic level consists of a particular organisms. It consists of producers, consumers, decomposers. The first trophic level consists of producers such as plants. The second trophic level consists of primary consumers. The third trophic level consists of secondary consumers. There are certain organisms which occupy more than one trophic level in the same ecosystem at the same time. An example include sparrow. It feeds upon grains. Hence, it is called as primary consumer and occupies second trophic level. It also feeds upon insects. Hence, it is called as secondary consumer and occupies third trophic level.

Thus, the correct answer is 'Sparrow.'

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Which of the following may occupy any trophic level in an ecosystem?

  1. Plankton

  2. Aquatic animals

  3. Decomposers

  4. Aquatic plants

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are various trophic levels in a food chain. The first trophic level consists of primary producers such as plant. The second trophic level consists of herbivores or primary consumers. The third trophic level consists of carnivores or secondary consumers. Decomposers are present at the top trophic level. Phytoplankton occupies the first trophic level in an ecosystem. The zooplankton feeding upon phytoplankton occupies the second trophic level in an ecosystem. Aquatic animals occupy any trophic level in an ecosystem. Aquatic animals such as zooplankton occupies first trophic level. Aquatic animals such as small fish occupies second trophic level. Aquatic animals such as large fish occupies third trophic level. The aquatic plants occupy first trophic level. 

Thus, the correct answer is 'Aquatic animals.'

Multiple choice evs - i insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

A group of interconnected food chains is called

  1. complex food chain

  2. food web

  3. food cycle

  4. pyramid of biomass

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A web of interconnected food chains is known as food web.

The food web has various interdependent food chains and establishes ecological balance.
So, the correct option is 'food web'.

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Trophic levels are formed by:

  1. plants only

  2. animals only

  3. organisms linked in food chains

  4. top consumers in food chain

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Trophic means food. The animals linked in the food chain form various trophic levels. A food chain is a series of organisms that eat and get eaten.

So, the correct option is 'organisms linked to the food chain'.

Multiple choice evs - i insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Which is not true about a complex food web?

  1. Populations tend to remain about the same size

  2. Energy levels remain about the same for all trophic levels

  3. Inputs are constant and outputs are minimal except for heat

  4. Most of the energy entering the system maintains the whole community

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10% of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat. Food webs illustrate how energy flows through ecosystems, including how efficiently organisms acquire and use it. Autotrophs, producers in food webs, can be photosynthetic or chemosynthetic. They use light energy to synthesize their own food, while chemoautotrophs use inorganic molecules. Heterotrophs cannot synthesize their own energy, but must obtain it from autotrophs in food webs.

So the correct option is 'energy levels remain about the same for all trophic levels.' 

Multiple choice evs - i insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

If we weighed all of the organisms at each level of this food web, which would be the heaviest?

  1. Grass and trees

  2. Grasshoppers and squirrels

  3. Hawks and foxes

  4. All levels would weigh the same

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

A food web consists of all the food chains in a single ecosystem. Each living thing in an ecosystem is part of multiple food chains. Each food chain is one possible path that energy and nutrients may take as they move through the ecosystem. All of the interconnected and overlapping food chains in an ecosystem make up a food web.  An ecosystem cannot support a large number of omnivores without supporting an even larger number of herbivores, and an even larger number of autotrophs and hence the biomass of autotrophs will be the heaviest as it present in abundant amount..

So the correct option is 'grass and trees'.

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Energy flow in an ecosystem begins with

  1. Omnivores

  2. Herbivores

  3. Decomposers

  4. Autotrophs

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.  Sun is the source of energy fixed by the photoautotrophs, called primary producers, like green plants. Primary consumers absorb most of the stored energy in the plant through digestion, and transform it into the form of energy they need, such as adenosine triphosphate (ATP), through respiration. A part of the energy received by primary consumers, herbivores, is converted to body heat (an effect of respiration), which is radiated away and lost from the system. 

So the correct option is 'autotrophs'.

Multiple choice evs insectivorous plants meaning of an ecosystem food chain and food web components of environment and their interdependencies

Humans and animals such as bears are biologically adapted to be

  1. Omnivores

  2. Herbivores

  3. Deteritivores

  4. Autotrophs

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

Omnivore is a consumption classification for animals that have the capability to obtain chemical energy and nutrients from materials originating from plant and animal origin. Often, omnivores also have the ability to incorporate food sources such as algae, fungi, and bacteria into their diet as well. Omnivores come from diverse backgrounds that often independently evolved sophisticated consumption capabilities. Although cases exist of herbivores eating meat and carnivores eating plant matter, the classification "omnivore" refers to the adaptations and main food source of the species in general. Various mammals are omnivores in the wild,  including humans and bear species.

So the correct option is 'omnivores'.