Two microbiology students performed the viable plate count exercise, as described in this lab manual. Both students performed the procedure using the same sample of pasteurized milk, however their final coliform and total bacterial colony counts varied greatly. Which of the following scenarios could have caused this variation?

A) Improper dilutions
B) Not mixing the milk before dilutions
C) Nonsterile water used for dilutions
D) Spreading the inoculum with a sterile spreader that had not cooled
E) Immediately inverting the inoculated plates
F) All of the above


F) All of the above

Biology & Microbiology

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The process of in situ hybridization is used for which of the following?

A. Cytogenetic mapping B. Physical mapping C. Linkage mapping

Biology & Microbiology

If the pattern remains the same, in 50 years the population in Figure 53-6 would:


a. be experiencing slow growth.
b. be experiencing rapid growth.
c. be experiencing steady state growth.
d. be experiencing negative growth.
e. No prediction could be made using these data.

Biology & Microbiology

Which is usually true of bacteria?

A. They are found as rods, spheres, or spirals. B. They reproduce by binary fission. C. They contain rigid cell walls made of peptidoglycan. D. They are found as single cells. E. All of the choices are correct.

Biology & Microbiology

Consider a plant where a multicellular generation is able to make both sperm and eggs. Which of the

following terms would describe such a plant?

a. homosporous b. bryophyte c. heterosporous d. lycophyte e. haploid/diploid

Biology & Microbiology