Gram-positive bacteria are bacteria that have thick cell walls which yield positive results in the Gram staining test. Lipoteichoic acid is a major component of the cell wall of gram-positive bacteria.
All bacteria indicated in the question can be classified by the Gram staining test:
Actinomycetes are Gram-positive bacteria
The genus <em>Arthrobacter </em>includes Gram-positive bacteria
<em>Escherichia coli </em>(<em>E. coli</em>) is a Gram-negative bacterium
<em>Staphylococcus spp.</em> are Gram-positive bacteria
<em>Bacillus spp</em> are Gram-positive bacteria
<em>Mycobacterium spp.</em> are Gram-positive bacteria
Prokaryotes can be divided into two domains: Bacteria and Archaea.
Gram staining is a method used to classify bacteria, but this method IS NOT USED to stain Archaea.
In consequence, I would not use the Gram test to stain Archaebacteria because Archaebacteria aren't bacteria (Option A is correct).
<span>I think the pKa for acetic acid is about 4.74. Therefore Acetic
acid/acetate buffer will work best at 4.74 +/- 1 pH unit and so the pH 8 is far
removed from that. Hence it would not buffer at that pH at all.</span>
