In the Gram stain, gram-positive bacteria are dark purple for all the following reasons EXCEPT: Thick peptidoglycan in the gram-positive cell wall prevents decolorization by alcohol The counterstain (safranin) causes the purple color to develop None of the other four answers (All are reasons that gram-positive bacteria are purple Crystal violet is fixed inside the cell as a CV-lodine complex once iodine is added The primary stain, crystal violet, is dark purple

What is the purpose of iodine in the Gram stain?   To act as a counterstain   None of the other choices   To rinse off excess reagent   To remove unstabilized crystal violet   To act as a mordant

Picture that has dark background with red cells is the Negative stain and other picture in white is the Acid fast stain. so far this is the information I have: gram stain: positive motility: motile oxygen requirement: Facultative anaerobe and than I need these two acid fast stain: _____??? negative stain: _____????

For a laboratory exercise of basic techniques in microbiology: Gram stain and Microscopy. What is the answer of table

How would you expect the staining properties of 24-hour culture of Bacillus subtilis or the other Gram-positive bacteria to compare to culture that is 3 to 4 days older?

In the Gram stain, gram-negative bacteria appear red for all the following reasons EXCEPT: They stain with safranin because they are colorless at the step where it is added Safranin is a red stain None of the other four answers (all are true) The peptidoglycan layer in their cell walls is too thin to retain the crystal violet-iodine complex when the decolorizer (alcohol) is added The gram-negative cells' outer lipopolysaccharide layer (outer membrane) prevents their being stained by crystal violet in the first step

Which of the following media selects for gram negative bacteria by inhibiting the growth of gram positives that typically incorporate its dye component into their relatively bigger cell walls?     blood agar     EMB     Mannitol salt agar     Simmon citrate agar     urease broth

Microscopic examination of a sample from a liquid bacterial culture intended to include only one species revealed the presence of both pink/red and purple cells after Gram staining. Discuss the basis of pink/red and purple cell appearance, and how would you avoid getting a mixed culture in future

Identify the cellular morphology for this Gram stain. What is the Gram reaction? What is the bacterial shape? What is the bacterial arrangement? What is the staining dye? [Choose ] [Choose ] Cocci Singles no arrangement Pleomorphic Chains Gram-negative Crystal Violet Phenol Red Bacilli Gram-positive Clusters Safranin

Which cellular structure is being detected in the motility test? bacterial ribosomes bacterial cilia gram negative cell wall bacterial flagella gram positive cell wall