UPSC Answer Key CAPF 2017
CAPF Answer Key 20174. The ecological niche of an organism relates to
A) Specific habitat of the organism
B) Symbiotic relationship with other organisms
C) Diverse Occurrence of species of under different conditions.
D) The interaction with all other organisms.
Answer: D) The interaction with all other organisms.
An ecological niche is a role and position a species has in its environment; how it meets its needs for food and shelter, how it survives, and how it reproduces. A species' niche includes all of its interactions with the biotic and abiotic factors of its environment.
5. Free swimming of microscopic animals in an aquatic environment are referred to as:
A) Plankton
B) Periphyton
C) Benthos
D) Nekton
Answer: D) Nekton
Nekton are swimming animals that can move freely and that are capable of migration from one place to another.
Benthos is the community of organisms that live on, in, or near the seabed, also known as the benthic zone.Plankton, the small and microscopic organisms drifting or floating in the sea or fresh water, consisting chiefly of diatoms, protozoans, small crustaceans, and the eggs and larval stages of larger animals. Many animals are adapted to feed on plankton, especially by filtering the water.
6. The term Biomagnification is referred to as:
A) Increase in the body weight
B) Uncontrolled growth of harmful organisms
C)Accumulation of increasing amount of nondegradable pollutant through food chain.
D) Increase in number of bacteria in culture medium
Answer: C)Accumulation of increasing amount of nondegradable pollutant through food chain.Biomagnification, also known as bio-amplification or biological magnification, is the increasing concentration of a substance, such as a toxic chemical, in the tissues of organisms at successively higher levels in a food chain.