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Observe the growth pattern in each tube below:    What is the oxygen class of the organism growing in Tube C? [a] Give an example of an organism (genus and species) that belongs in this oxygen class: [b] What is the oxygen class of the organism growing in Tube E? [c] Give an example of an organism (genus and species) that belongs in this oxygen class: [d]

Which of the following safety practices are required for BSL-2 laboratories? Select all that apply!

Serial ten-fold dilutions are made from a broth culture of Erwinia carotovora in order to determine the number of bacteria in the culture. The dilution scheme is illustrated below:  What is the dilution in Tube D?

Name the morphology of the bacterial cells in the diagrams below: [a] [b] [c]

Serial ten-fold dilutions are made from a broth culture of Erwinia carotovora in order to determine the number of bacteria in the culture. The dilution scheme is illustrated below:  What is the dilution in Tube C?

Serial ten-fold dilutions are made from a broth culture of Bacillus subtilis in order to determine the number of bacteria in the culture.  Following the dilution series, 0.1 ml of a 1:10,000 (1 x 10-4) dilution is plated, the plate is incubated, and 110 colonies are counted.  Calculate the number of bacteria in the original Bacillus subtilis culture. Don’t forget units! Cannot earn full credit without proper units. Make sure your answer reflects proper scientific notation! Use the ^ to denote an exponent, i.e. 1 x 10-4 would be written as 1 x 10^-4.

Serial ten-fold dilutions are made from a broth culture of Bacillus subtilis in order to determine the number of bacteria in the culture.  Following the dilution series, 0.1 ml of a 1:10,000 (1 x 10-4) dilution is plated, the plate is incubated, and 110 colonies are counted.  Calculate the number of bacteria in the original Bacillus subtilis culture. Don’t forget units! Cannot earn full credit without proper units. Make sure your answer reflects proper scientific notation! Use the ^ to denote an exponent, i.e. 1 x 10-4 would be written as 1 x 10^-4.

These cells were stained using one of the differential staining protocols we covered in lab.  What was cellular structure was decolorized during the decolorizer step of this staining technique? 

Four different species of bacteria were streaked on this EMB plate and incubated. What conclusion(s) can be draw about species A?   

These cells underwent one of the differential staining protocols we covered in lab. Which bacterial genus do these cells most likely belong to?