UPSC CSE Prelims
Question 50
With reference to the food chains in ecosystems, which of the following kinds of organism is/are known as decomposer organism/organisms?
- Virus
- Fungi
- Bacteria
Select the correct answer using the codes given below.
View correct answer and explanation
Correct answer: B
Correct Option: B
Explanation: Fungi and bacteria are the principal biological decomposers that mineralise dead organic matter. Viruses require host cells and are not treated as decomposer organisms.
Statement/Pair-wise Analysis:
Statement/Item 1: Incorrect - Viruses cannot independently digest and mineralise dead matter.
Statement/Item 2: Correct - Many fungi secrete enzymes that break down plant and animal remains.
Statement/Item 3: Correct - Saprotrophic bacteria recycle organic matter into inorganic nutrients.
Option-wise Analysis:
A: Incorrect - includes false item 1 and excludes true items 2, 3.
B: Correct - selects all and only the accurate statements/pairs.
C: Incorrect - includes false item 1 and excludes true item 2.
D: Incorrect - includes false item 1.