Question

lichens also provides litmus paper while making this paper that time also does it contain the algae and fungi

Answer 1

Litmus is a water soluble dye extracted from lichens. In the process of obtaining litmus, lichens are ground and mixed into the solution of sodium carbonate and ammonia. It is left for few weeks and then lichen pieces are filter out from the mixture. The extract which is obtained is litmus. When this litmus is absorbed into a strip of filter paper, it becomes litmus paper. Thus there is no chance of having any remains of algae or fungi inside litmus paper.