Question

Please don’t answer if you’re not absolutely sure. Please elaborate. Is it specificity only or both?

Please define sensitivity and specificity

Would remoring bile salts andor crystal violet from MacConkey agar alter the medium's senstuityor specificity? Explain your answer.(See pages 8 and 9, "A Word About Experimental Design," for assistance with these terms.)

Answer 1

ANSWER:

Removing bile salts and/or crystal violet from MacConkey Agar alter the specificity of the medium.

MacConkey agar is a selective and differential culture media used for the isolation of Gram-negative bacteria. Bile salts and crystal violet are selective agents in MacConkey agar for gram negative bacteria and Gram positive bacteria are inhibited by selective agents in MacConkey.

Removing bile salts and/or crystal violet from MacConkey Agar alter the specificity of the medium. As bile salts and crystal violet would inhibit the growth of gram positive bacteria. Removing of bile salts and crystal violet makes MacConkey agar no longer selective and reduces its specificity and allows growth of gram positive bacteria.

Sensitivity means getting false negatives, in the above condition we will not get such results.