Ecology, Ecosystem - GS questions based on daily current affairs

1)   Which of the following statement/s is/are correct regarding ecological succession?

1) Ecological succession is brought about both by the activities of the communities as well as by the physical environment in that particular area.
2) Primary Succession is faster than Secondary Succession.

a. Only 1
b. Only 2
c. Both 1 and 2
d. None of the above
Answer  Explanation 

ANSWER: Only 1

Explanation:
The process by which communities of plant and animal species in an area are replaced or changed into another over a period of time is known as ecological succession. Primary succession takes place an over a bare or unoccupied areas such as rocks outcrop, newly formed deltas and sand dunes, emerging volcano islands and lava flows as well as glacial moraines (muddy area exposed by a retreating glacier), where no community has existed previously. A secondary succession is relatively fast as the soil has the necessary nutrients as well as a large pool of seeds and other dormant stages of organisms.
2)   Which of the following ecological pyramid/pyramids can be inverted?

1) Pyramid of number
2) Pyramid of biomass
3) Pyramid of energy

a. Only 2 and 3
b. Only 1 and 2
c. All of the above
d. None of the above
Answer  Explanation 

ANSWER: Only 1 and 2

Explanation:
Ecological pyramids are the graphic representations of trophic levels in an ecosystem.
They are pyramidal in shape and they are of three types: The producers make the base of the pyramid and the subsequent tiers of the pyramid represent herbivore, carnivore and top carnivore levels. Energy pyramids are never inverted. In most of the terrestrial ecosystems the pyramid of biomass is upright. However, in case of aquatic ecosystems the pyramid of biomass may be inverted. In some instances the pyramid of number may be inverted, i.e. herbivores are more than primary producers as you may observe that many caterpillars and insects feed on a single tree.
3)   Which of the following statement/s is/are correct regarding human modified ecosystems?

1) Even if they are Human modified ecosystems, they depend on solar energy.
2) Human modified Ecosystems are complex and unstable.

a. Only 1
b. Only 2
c. Both 1 and 2
d. None of the above
Answer  Explanation 

ANSWER: None of the above

Explanation:
Human modified ecosystems may or may not depend on solar energy e.g. in an industry energy is provided in the form of fossil fuel or electricity or both. They are highly simplified, have low species diversity and are highly unstable. Some examples of human modified ecosystems are: Agro-ecosystems, Plantation forests, Urban ecosystems, Rural ecosystems, Aquaculture, Industrial areas, Laboratory cultures, etc.

Related Content

▲