Chapter 22, Problem 3STP

Summary Introduction

Introduction:

Lichens are bioindicators, they cannot survive in polluted areas. Lichens are the mutualistic association of the fungi and cyanobacterium or algae

Answer to Problem 3STP

Correct answer:

The correct answer is option (A) air quality decreases.

Explanation of Solution

Explanation/justification for the correct answer:

Option (A)air quality decreases. Lichens absorb nutrients from the air and they are sensitive to sulfur. In case, the sulfur dioxide, which is one of the major pollutants increases in the air, lichens would not grow and disappear. So, the absence of lichen could be due to a decrease in air quality.So, the correct answer is option (A).

Explanation for incorrect answer:

Option (B)annual temperature decreases. Lichens are the bioindicators for air pollution. They cannot survive in polluted air. Therefore, the temperature is not related. So, this is an incorrect option.

Option (C)humidity pattern changes. Lichens are the bioindicators for air pollution. They cannot survive in polluted air. It may also be affected by the environmental temperature of a certain area but it is not related to humidity. So, this is an incorrect answer.

Option (D)rainfall pattern. The lichen does not involve in the rainfall pattern directly.So, this is an incorrect answer.