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

The passage implies that

Directions: Read the following passage and answer the related question.

The stability of the system of living creatures is linked with the natural food chain. Plants produce carbohydrates and protein and are eaten by herbivorous animals. We know the importance of all the organisms involved in this predator-prey food chain. By introducing toxic chemicals, which will be passed on to man through the food chain, or by destroying any of the species, we are only creating trouble for ourselves.

An interesting example is the ladybird beetle brought from Australia to California to prevent cottony-cushion scale insects infecting citrus plants there. The beetle ate up the insects and the situation improved. But recently DDT sprayed to control the other pests in the citrus trees affected the beetle and the cottony-cushion scales are dangerously active again.

To save crops, we kill sparrows and the insects multiply. It is said that one of the European countries which did this had to import sparrows to control the insects. Kill all the snakes in India because they are dangerous, and tomorrow you may have to import snakes to kill rats.

  1. man is on the verge of extinction

  2. birds, animals and fish are created for man’s food

  3. food chain must remain unaltered

  4. one should be careful in disturbing the food chain
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the main theme of the passage.

Multiple choice

The main limiting factor on the population of organisms is

Directions: Read the following passage and answer the related question.

The stability of the system of living creatures is linked with the natural food chain. Plants produce carbohydrates and protein and are eaten by herbivorous animals. We know the importance of all the organisms involved in this predator-prey food chain. By introducing toxic chemicals, which will be passed on to man through the food chain, or by destroying any of the species, we are only creating trouble for ourselves.

An interesting example is the ladybird beetle brought from Australia to California to prevent cottony-cushion scale insects infecting citrus plants there. The beetle ate up the insects and the situation improved. But recently DDT sprayed to control the other pests in the citrus trees affected the beetle and the cottony-cushion scales are dangerously active again.

To save crops, we kill sparrows and the insects multiply. It is said that one of the European countries which did this had to import sparrows to control the insects. Kill all the snakes in India because they are dangerous, and tomorrow you may have to import snakes to kill rats.

  1. general climate

  2. sunlight

  3. soil condition

  4. food chain
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

As discussed in the passage, all living beings depend on each other and control the population, and this is the food chain. If one animal in the chain is taken out, the ones lower down multiply and those above suffer.

Multiple choice

The example of the ladybird shows that

Directions: Read the following passage and answer the related question.

The stability of the system of living creatures is linked with the natural food chain. Plants produce carbohydrates and protein and are eaten by herbivorous animals. We know the importance of all the organisms involved in this predator-prey food chain. By introducing toxic chemicals, which will be passed on to man through the food chain, or by destroying any of the species, we are only creating trouble for ourselves.

An interesting example is the ladybird beetle brought from Australia to California to prevent cottony-cushion scale insects infecting citrus plants there. The beetle ate up the insects and the situation improved. But recently DDT sprayed to control the other pests in the citrus trees affected the beetle and the cottony-cushion scales are dangerously active again.

To save crops, we kill sparrows and the insects multiply. It is said that one of the European countries which did this had to import sparrows to control the insects. Kill all the snakes in India because they are dangerous, and tomorrow you may have to import snakes to kill rats.

  1. cottony-cushion scales should be allowed to eat citrus freely

  2. by destroying even one species we create problems

  3. rats must be protected from snakes

  4. lions should have limited access for hunting deer

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

The other options are either given as examples or warnings.

Multiple choice

In an energy pyramid, which trophic level will transfer the highest amount of energy to the next tropic level?

  1. I

  2. II

  3. III

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

First tropic level in an energy pyramid represents producers which contain the highest amount of energy. Therefore, the first trophic level will transfer the highest amount of energy to the next trophic level. Since only 10% of the energy is transferred to the next trophic levels, the higher trophic levels will have less amount of energy as compared to the first trophic level. 

Multiple choice

Which of the following options correctly represents the arrangement of organisms in increasing order of concentration of heavy metals in their body?

A study found a particular heavy metal contaminating a lake. The given illustration depicts a food chain existing in the lake. 

Phytoplankton -----> Zooplankton -----> Smelt -----> Lake trout -----> Herring gull

  1. Lake trout < Phytoplankton < Zooplankton < Smelt < Herring gull

  2. Phytoplankton < Zooplankton < Smelt < Lake trout < Herring gull

  3. Zooplankton < Phytoplankton < Smelt < Herring gull < Lake trout

  4. Smelt < Zooplankton < Phytoplankton < Herring gull < Lake trout
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The concentration of heavy metals in the body of the organisms increases with the increase in trophic level. Since phytoplanktons are present at the lowermost trophic level, the concentration of heavy metals in phytoplanktons will be minimum, while the concentration of heavy metals in herring gull will be the highest as it is present at the highest trophic level. Hence, the correct order of organisms with increasing levels of heavy metals is option 2.

Multiple choice

Which of the following statements about detritivores is/are correct?

  1. They feed on the dead.

  2. They obtain nutrients by consuming detritus.

  3. Both 1 and 2

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Detritivores, also known as detritophages, detritus feeders, or detritus eaters, are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces).

Multiple choice

The term biological magnification refers to the increased levels of a toxin seen in successive trophic levels in a food web. Which one of the following options correctly states the reason(s) for the increment of a toxin in the ecosystem?

  1. The toxin is highly toxic to primary producers, relatively less toxic to primary consumers, and non-toxic to secondary consumers. Thus, a higher level of toxin is seen in species representing higher trophic levels.

  2. The toxin cannot be degraded by microorganism and consequently persist in the environment for years.

  3. The toxin to begin with was not toxic or less toxic, but became more toxic by metabolism in the primary producers.

  4. Both (2) and (3)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Biological magnification occurs because persistent environmental toxins cannot be easily degraded by microorganisms or metabolized by organisms, causing them to accumulate and magnify in concentration up the food chain.

Multiple choice plant kingdom biology

What are examples of primary producers?

  1. Omnivores

  2. Animals

  3. Green plants and Algae

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

Primary producers in a terrestrial ecosystem live in and around the organic matter. Since they are not mobile, they live and grow where there are nutrients to sustain them. The primary producers include green plants, lichens, moss, bacteria, and algae. 

Multiple choice evs animal- the base of our life uses of animals agro-complimentary occupations improvement of crop production animal husbandry

Goats feed on ..........

  1. Low herbs

  2. Grass

  3. Low shrubs

  4. Shrubs and low trees
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

There are a number of shrubs and low trees that are used for ruminant fodder. Many are nitrogen-fixing, meaning that they can help to regenerate nitrogen depleted soils, and many are also excellent soil binders. As fodder, nitrogen-rich species are generally highly palatable and rich in protein and provide excellent supplementation for goats that are ill or weak, or when forage is not of good quality.

Multiple choice

What role does the lizard play in the food web below?

  1. Producer

  2. Decomposer

  3. Consumer

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A lizard is an animal that must eat other organisms (like insects or plants) to obtain energy, making it a consumer in a food web. Producers make their own food, and decomposers break down dead organic matter.