Part I: Basic Bacteriology
You’re watching a television program that is discussing viruses called bacteriophages that can kill bacteria. Your roommate says, “Wow, maybe viruses can be used to kill the bacteria that infect people! You’re taking the Microbiology course now; what’s the difference between viruses and bacteria?” Which one of the following would be the most accurate statement to make?
(A) Viruses do not have mitochondria, whereas bacteria do.
(B) Viruses do not have a nucleolus, whereas bacteria do.
(C) Viruses do not have ribosomes, whereas bacteria do.
(D) Viruses replicate by binary fission, whereas bacteria replicate by mitosis.
(E) Viruses are prokaryotic, whereas bacteria are eukaryotic.
Bacteria, fungi (yeasts and molds), viruses, and protozoa are important causes of human disease. Which one of the following microbes contains either DNA or RNA but not both?
Which one of the following contains DNA that is not surrounded by a nuclear membrane?
The initial step in the process of many bacterial infections is adherence of the organism to mucous membranes. The bacterial component that mediates adherence is the:
In the Gram stain procedure, bacteria are exposed to 95% alcohol or to an acetone/alcohol mixture. The purpose of this step is:
(A) to adhere the cells to the slide
(B) to retain the purple dye within all the bacteria
(C) to disrupt the outer cell membrane so the purple dye can leave the bacteria
(D) to facilitate the entry of the purple dye into the gram-negative cells
(E) to form a complex with the iodine solution