Tag: ecosystems

Questions Related to ecosystems

Which one of the following is a major link in decomposer food chain?

  1. Anthracoceros

  2. Gyps

  3. Anser

  4. Pavo


Correct Option: B
Explanation:

Gyps is a genus of vultures characterized by bald head, broad wings and mainly dark plumage. They are large scavenging birds, feeding mostly from carcasses of dead animals and thereby forming an important link in the decomposes food chain.
Thus, the correct answer is (B) Gyps.

In summers, decomposition proceeds faster than in

  1. Spring

  2. Winter

  3. Autumn

  4. Hot weather


Correct Option: B

50% of incident energy is lost due to:

  1. Consumers

  2. Producers

  3. Microorganisms

  4. Planktons


Correct Option: B

Presence of hydrogen sulphide indicates anaerobic

  1. Decomposition

  2. Eutrophication

  3. Degradation

  4. Biodegradation


Correct Option: A

The correct match among the following is

  1. Producers--- act upon the decomposed substances and transform them into different forms of inorganic and organic substances

  2. Consumers--- are autotrophic members of ecosystem

  3. Decomposers--- feed upon dead decaying living organisms and break them into simpler compounds fit for use of producers

  4. None of the above


Correct Option: C
Explanation:

The green plant in the ecosystem-terminology are called as producers. All animals depend on plants (directly or indirectly) for their food needs. They are hence, called as consumers and also heterotrophs. 

Decomposers are organisms, that break down dead or decaying organisms, and carry out the natural process of decomposition. Like herbivores and predators, decomposers are heterotrophic, meaning that they use organic substrates to get their energy, carbon and nutrients for growth and development.

The breakdown of detritus into smaller particles by earthworm is a process called as

  1. Humification

  2. Fragmentation

  3. Mineralisation

  4. Catabolism


Correct Option: B
Explanation:

Steps of decomposition are: 

a. Fragmentation: It is the breakdown of detritus into smaller particles by detritivores (e.g., earthworm). 
b. Leaching: By this process, water soluble inorganic nutrients go down into the soil horizon and get precipitated as unavailable salts. 
c. Catabolism: Degradation of detritus into simpler inorganic substances by bacterial and fungal enzymes. Fragmentation, leaching and catabolism operate simultaneously on the detritus. 
d. Humification: Accumulation of humus (dark amorphous substance) in soil. Humus is resistant to microbial action and so decomposes very slowly.
e. Mineralization: It is the release of inorganic nutrients due to the degradation of humus some microbes.

Earthworm is said to decompose detritus substances.

  1. True

  2. False

  3. Ambiguous

  4. Data insufficient


Correct Option: A
Explanation:

Earthworm is an important organism in the process of decomposition. It is said to decompose detritus substances thus said to be a detrivore.

A pollution free stream within a few miles downstream of a point at which a small amount of sewage is being dumped into it. This is the result of

  1. Succession

  2. Eutrophication

  3. Evaporation

  4. Photosynthesis

  5. Decomposition


Correct Option: E
Explanation:
Presence of decomposers (bacteria) in sewage leads to decomposition of complex organic compounds of sewage into simpler substances. These simpler substances are then consumsed by the decomposers as source of organic compounds. Hence, decomposition of organic compounds and utilization of simper substances by decomposers might have led to formation of pollution free stream out of a sewage dump. 
The process of change in ecological community of an area over time which in turn results in formation of climax community is termed as succession; it does not remove pollutants from the habitat.  
Eutrophication means increased pollutant due to algal blooms as supported by presence of excess organic compounds in water. 
Complex organic substances can not be evaporated. 
Photosynthesis is carried out by autotrophs while sewage is mostly occupied by decomposers. 
Therefore, the correct answer is option E.