Question

Please look at these two photos of an unknown gram positive and gram negative bacteria that were Gram stained. What is the morphology/characteristics of these unknown bacteria?

AA

Answer 1

Solution:-

We know that baceria can be identified or differentiated in to two groups by gram staining. They are Gram positive (+) and Gram negative (-).

Gram positive bacteria stain voilet upon staining due to the presence of thick layer of peptidoglycan which retains crystel violet. Where as Gram negative bacteria stains red due to thinner peptidoglycan layer.

so the first picture we see in red is gram negative bacteria which has thinner peptidoglycan layer. They are also seen as rod shaped in appearance. So they may be belong to bacterial group Bacilli ( rod shaped bacteria).

the second picture we see in violet is gram positive bacteria which has thicker peptidoglycan layer. They are seen in spherical shape. and also grape like structure. So they are actually belong to the bacterial group Staphylococcus