BIOL 106Lab 9 Eaxm GRADED A

BIOL 106Lab 9 Eaxm




BIOL 106Lab 9
Eaxm



Lab 9 Eaxm
1. Given Culture A and Culture B were accidentally mixed, what observations were made
from the Gram stain (shown below)?


Gram-positive cocci (spherical) clusters and Gram-negative bacillus (rods) were observed.




2. Given the results from a MacConkey agar plate shown below, what is the shape of
Culture A? Culture B?

MacConkey agar is selective for Gram-negative bacteria. Thus, Culture A must be Gram-
positive as no growth was observed. Coupled to the results of the gram stain, Culture A
(Gram-positive) must be the cocci.

, BIOL 106Lab 9 Eaxm
Culture B must be Gram-negative (growth observed) and this correlates to the bacillus or
rod-shaped bacteria.