1. Introduction to Microbiology

Which of the following shows the best order of steps of the scientific method?

A scientist observes that even after sterilizing a broth, cells reappear in the broth over time. The scientist then asks:'Why do cells reappear in the broth after sterilization?' and designs/conducts an experiment. Considering this, appropriately label each of the following blanks as either a 'prediction, hypothesis or theory.'

________________:Cells will only appear in the broth exposed to a source of preexisting cells.

________________:Cells appear only when preexisting cells grow & divide; therefore, cells only appear in exposed broths.

________________:All organisms consist of cells & all cells come from preexisting cells.

Which of the following statements about the cell theory is false?

Identify the following statements as observations or conclusions.

a. The solution turned red.

b. The bacterium is a rod shape.

c. The cell died due to lack of nutrients.

d. The bacterium is E. coli.

e. The cell is Gram-positive.

f. The bacterium is a pathogen.

g. There are small green structures present upon performing the endospore stain.

h. The solution remained clear after 10 hours of incubation.

i. Fermentation occurred.

j. Life comes from life.

Refer to the four steps in the scientific method in describing Pasteur’s fermentation experiments.

A local newspaper writer has contacted you, an educated microbiology student from a respected college. He wants to obtain scientific information for an article he is writing about “life” and poses the following query: “What is the difference between a living thing and a nonliving thing?” Knowing that he will edit your material to fit the article, give an intelligent, scientific response.