Question
Read the following and answer any four questions from (i) to (v) given below:

Excessive exploitation of species, whether a plant or animal reduces the size of its population so it becomes vulnerable to extinction. Such as Dodo and passenger pigeon have become extinct due to over exploitation by humans. Thus the world is facing accelerated rates of species extinctions, largely due to human interference.

  1. Which of the following cause of biodiversity loss is not included in evil quartet?
  1. Coextinction.
  2. Pollution.
  3. Alien species invasion.
  4. Habitat loss and fragmentation.
  1. Identify the species that have become extinct due to over exploitation.
  1. Stellar sea cow.
  2. Yucca moth.
  3. Blatta orientalis.
  4. Nile Perch.
  1. Factors which make species susceptible to extinction are:
  1. Large population size.
  2. Lack of genetic variability.
  3. Ower status of trophic level.
  4. Ability to switch over to ahem ate foods.
  1. Assertion: Pollution reduces species biodiversity.

Reason: Spill over of oil in sea causes death of several marine animals.

  1. Both assertion and reason are true and reason is the correct explanation of assertion.
  2. Both assertion and reason are true but reason is not the correct explanation of assertion.
  3. Assertion is true but reason is false.
  4. Both assertion and reason are false.
  1. ________ is the first major cause of species extinction.
  1. Coextinction.
  2. Over exploitation.
  3. Habitat destruction.
  4. Alien species invasion.

Answer

  1. (b) Pollution

Explanation:

Evil quartet, i.e., four major causes of biodiversity loss are habitat loss and fragmentation, over exploitation, alien species invasion and co-extinction.

  1. (a) Stellar sea cow.
  1. (b) Lack of genetic variability.

Explanation:

Population traits which make species susceptible to extinction are: small population, higher status of trophic level and inability to switch over to alternate foods.

  1. (a) Both assertion and reason are true and reason is the correct explanation of assertion.
  1. (c) Habitat destruction.

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