Lichens, which are capable of initiating ecological succession even on a bare rock, are actually a Symbiotic association of

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Q: 22 (IAS/2014)
Lichens, which are capable of initiating ecological succession even on a bare rock, are actually a Symbiotic association of

question_subject: 

Science

question_exam: 

IAS

stats: 

0,233,83,33,233,20,30

keywords: 

{'lichens': [0, 0, 0, 3], 'ecological succession': [1, 0, 0, 0], 'fungi': [1, 1, 2, 3], 'algae': [2, 0, 0, 0], 'symbiotic association': [0, 0, 0, 1], 'mosses': [1, 0, 0, 4], 'bacteria': [4, 1, 2, 3]}

The correct answer is "algae and fungi". Lichens are composite organisms consisting of a symbiotic association of a fungus with a photosynthetic partner, which is usually an alga but can also be a cyanobacterium. The fungus provides a protective environment and the necessary nutrients for the alga to carry out photosynthesis, while the alga provides organic carbon for the fungus. This association allows lichens to colonize and grow on harsh substrates such as rocks, and they are often the first organisms to establish in a newly created habitat.