1) What do u mean by Litmus paper ?

Paper stained with litmus which is used to indicate the acidity or alkalinity of a substance.

(sorry i just like short answers)-,-

Litmus paper is a filter paper that has been treated with a lichen-provided natural-soluble dye. Litmus paper is a piece of paper that produces a result which can be used as a pH indicator. Litmus is mainly used to assess whether a solution is acidic or basic.

not sure if this is what you'r looking for eubacteria and archaebacteria

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products