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

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
A Correct answer
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.

Multiple choice

Identify one food chain represented in this ecosystem

  1. alligator, moorhen, plants

  2. plants, deer, bobcat

  3. plants, pig frog, bobcat

  4. all the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A food chain represents a linear sequence of organisms where nutrients and energy are transferred from one to another. Option B correctly identifies a producer (plants) being eaten by a primary consumer (deer), which is then eaten by a secondary consumer (bobcat).

Multiple choice

What do the arrows represent?

  1. primary producers

  2. breaking down organisms

  3. energy flow

  4. where the animals go
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In food webs and food chains, arrows are used to indicate the direction of energy transfer from the organism being eaten to the organism that consumes it.

Multiple choice

Humans are generally

  1. carnivores

  2. herbivores

  3. omnivores

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

Humans are biologically adapted to consume both plant and animal matter, which classifies them as omnivores.