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Which of these statement/s about lichens...

Which of these statement/s about lichens is/are ture?
I. Lichens are mutually beneficial symbotic associations.
II. They grow extensively in area with high pollution, hence called as pollution indicators.
III. The phycobiont member, algae, is an autotroph and the mycobiont member, fungi, is a heterotroph.
IV. Fungi help the algae harvest sunlight for photosynthesis.

A

II and III

B

I and III

C

I, II and III

D

III and IV

Text Solution

AI Generated Solution

The correct Answer is:
To determine which statements about lichens are true, we will evaluate each statement one by one. **Step 1: Evaluate Statement I** - Statement I: "Lichens are mutually beneficial symbiotic associations." - Explanation: Lichens are indeed formed by a symbiotic relationship between fungi (mycobiont) and algae or cyanobacteria (phycobiont). In this relationship, both organisms benefit: the algae/cyanobacteria perform photosynthesis and provide food, while the fungi provide protection and absorb minerals from the environment. - Conclusion: This statement is **true**. **Step 2: Evaluate Statement II** - Statement II: "They grow extensively in areas with high pollution, hence called as pollution indicators." - Explanation: Lichens are actually sensitive to pollution, particularly sulfur dioxide and other pollutants. They do not thrive in polluted areas; rather, their presence indicates clean air. Therefore, they are considered pollution indicators because their absence often signifies high pollution levels. - Conclusion: This statement is **false**. **Step 3: Evaluate Statement III** - Statement III: "The phycobiont member, algae, is an autotroph and the mycobiont member, fungi, is a heterotroph." - Explanation: This statement is correct. The phycobiont (algae or cyanobacteria) is an autotroph because it can produce its own food through photosynthesis. The mycobiont (fungi) is a heterotroph, as it absorbs nutrients from the environment. - Conclusion: This statement is **true**. **Step 4: Evaluate Statement IV** - Statement IV: "Fungi help the algae harvest sunlight for photosynthesis." - Explanation: This statement is misleading. While fungi do provide support and absorb nutrients, they do not assist in harvesting sunlight for photosynthesis. The algae themselves are responsible for capturing sunlight and performing photosynthesis. - Conclusion: This statement is **false**. **Final Conclusion:** - The true statements are I and III. Therefore, the correct answer is that the true statements about lichens are **I and III**.
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