Tag: forests: our lifeline

Questions Related to forests: our lifeline

Which of the following helps in the formation of humus?

  1. Earthworm

  2. Lion

  3. Birds

  4. None of the above


Correct Option: A

Which organism will be affected in the absence of the decomposers?

  1. Plants

  2. Animals

  3. Insects

  4. All of these


Correct Option: D
Explanation:

Decomposers are the organisms that play a critical role by breaking down and decomposing the body and release the element back to nature for other organisms. Thus they help in recycling the nutrients in the atmosphere. They also act as the cleaning agent of the environment because without them dead organisms will pile up. Thus in their absence all the organisms i.e., plants, animals, and insects will be affected. Thus, the correct answer is option D.

Which of the following pair is incorrect?

  1. Orange - Glandular hair

  2. Pomegranate - Testa

  3. Pear - Thalamus

  4. Mango - Seed


Correct Option: A

Scattering of seeds over a wide area is called ...........

  1. Pollination

  2. Fertilisation

  3. Dispersal

  4. Germination


Correct Option: C
Explanation:

  1. Transfer of pollen grains from the anther to the stigma of either same of a different flower of the same or different plant is pollination.
  2. The fusion of male and female gametes is known as fertilization.
  3. Scattering of seeds over a wide area by animals or other means is called dispersal.
  4. Growing of a new plant from seed under the favorable condition is known as germination.
So the correct option is "Dispersal".

A detrivorous animal of economic importance is

  1. Caterpillar larva

  2. Leech

  3. Earthworm

  4. Giriraja fowl


Correct Option: C
Explanation:

Detrivores are those animals which obtain their nourishment by consuming decomposing plant and animal parts. Earthworms decompose the organic matter of soil thus aerating it which is then used by farmers as fertilizers. Thus it improves the fertility of soil making it more porous. 

Caterpillar larva feeds on leaves.
Leech is sanguivores which means blood sucking organism.
Giriraja fowl feeds on small insects and grass.
Thus, the correct answer is option C. 

Bacteria and fungi in a forest ecosystem are generally 

  1. Producers

  2. Decomposers

  3. Primary consumers

  4. Secondary consumers

  5. Tertiary consumers


Correct Option: B
Explanation:

Decomposers are saprotrophs which decompose the organic remains by secreting extracellular digestive enzymes. Due to degradation of organic remains, decomposers are also called reducers. They are also known as mineralisers as they release minerals trapped in organic remains. Bacteria and fungi, in general microorganisms, are usually detrivores that feed on dead and decaying organic matter and act as decomposers.

The bacteria that attack dead organic matter are

  1. Producers

  2. Herbivores

  3. Carnivores

  4. Decomposers


Correct Option: D
Explanation:

Decomposers are organisms feeding on dead remains of plants and animals and excreta of animals. Decomposers are saprotrophs, which decompose the organic remains by secreting extracellular digestive enzymes. Due to degradation of organic remains, decomposers are also called as reducers. They are also known as mineralizers, as they release minerals trapped in organic remains.

Microorganisms are

  1. Primary consumers

  2. Secondary consumers

  3. Tertiary consumers

  4. Decomposers


Correct Option: D
Explanation:
  • The food chain starts with energy from the sun, which is captured by plants and converted into fuel through photosynthesis. 
  • Primary consumers eat plants, and secondary and tertiary consumers feed on primary consumers. At the end of the chain, a group of micro-organisms called as decomposers carry out natural process of decomposition and form the final link in the food chain. They break down dead animals and plants and return vital nutrients to the soil.
  • So, option D is correct here.

Decomposers are

  1. Autotrophs

  2. Heterotrophs

  3. Autoheterotrophs

  4. Organotrophs


Correct Option: B
Explanation:

Decomposers are heterotrophs feeding on the dead and decaying matter. More specifically decomposers are saprotrophs, which decompose the organic remains by secreting extracellular digestive enzymes. Due to degradation of organic remains, decomposers are also called as reducers. They are also known as mineralizers, as they release mineral trapped in organic remains.

Extinction of flora and fauna can be caused by 

  1. Aforestation

  2. Deforestation

  3. Reforestation

  4. None of the above


Correct Option: B
Explanation:
1. Deforestation is the permanent destruction of forests in order to make the land available for other uses like farms, ranches, or urban. so that time of flora and fauna can face extinction. 
2. Reforestation is the process of replanting an area with trees.
3. Afforestation is the process of adding trees to an area.
So, the answer is "deforestation".