Q. Consider the following statements regarding “lichens”:
1.It is a combination of an alga and bacteria.
2.They are found in rivers and ground water.
Which of the statements given above is/are correct?
Explanation: A lichen is a peculiar combination of an alga and a fungus– the two live deriving mutual benefit.
- They are group of greyish green plants which grow on rocks, tree-trunks, dead wood, etc.
- The algae manufacture food which becomes available to the fungus, and the absorbs and retains water and thus keeps the algal cells moist. A example of symbiosis.
- They are most common in wetlands, rare in rivers and streams and are not found in ground water.
Source: Shankar IAS Environment book