WGU D311 Fundamentals of Microbiology Final Exam Review

WGU D311 Fundamentals of Microbiology Final Exam Review Which statement describes prokaryotic cells? a) Prokaryotic cells are found in coccus form in both pairs and clusters. b) Prokaryotic cells have multiple rod-shaped chromosomes. c) Prokaryotic cells are found in chains of rods but not single rods. d) Prokaryotic cells have a nucleus surrounded by a complex nuclear membrane. Which statement describes eukaryotic cells? a) The exoskeletons of eukaryotic cells maintain and support the cells' shapes. b) The nuclei of eukaryotic cells are surrounded by complex nuclear membranes. c) The genomes of eukaryotic cells are usually packaged in single circular chromosomes. d) The organelles of eukaryotic cells are held in place by semipermeable exoskeletons. Which statement describes eukaryotic flagella? a) Eukaryotic flagella can cover the entire surface of a cell. b) Eukaryotic flagella are rotating structures. c) Eukaryotic flagella have twelve pairs of microtubules. d) Eukaryotic flagella are flexible, whip-like structures. Which statement describes the endomembrane system? a) It is attached to the smooth endoplasmic reticulum and makes proteins for insertion into the cell membrane. b) It includes the Golgi apparatus, lysosomes, and vesicles. c) It is a system that uses diffusion to transport materials inside of the cell. d) It lacks membrane-bound organelles. Which statement accurately describes similarities between protozoa and fungi? a) Both perform chemosynthesis. b) Both can be harmful or harmless depending on the context. c) Both are made of long filaments that form visible colonies. d) Both move with help from cilia and flagella. Why are algae considered photosynthetic organisms? a) Algae cell walls are constructed with a material called peptidoglycan. b) Algae contain substances that can be converted into biofuels. c) Algae produce chemical energy from the sun's light energy. d) Algae create waste products that other organisms can use to make energy. Why are plasmids important to the survival of organisms? a) Plasmids exclusively contain the genes responsible for cellular replication in bacteria. b) Plasmids can store excess nutrients in the cytoplasm of the cell. c) Plasmids protect the bacterial genome in a dormant state during unfavorable environmental conditions. d) Plasmids carry genetic material, apart from the genome, that can benefit the organism. Which statement describes bacteria? a) Some bacteria are eukaryotes. b) Some bacteria have cell walls composed of mycolic acid. c) Some bacteria are motile by cilia. d) Some bacteria have cell walls composed of chitin. Why are prokaryotes vital to life? Which aspect of nutrient cycling is performed only by prokaryotes? a) Respiration process b) Carbon fixation c) Nitrate assimilation d) Nitrogen fixation How does microbial bioremediation benefit the environment? a) By helping to minimize the growth of pathogens in different parts of the body b) By helping to metabolize and remove pollutants in the atmosphere c) By producing complex organic pharmaceutical compounds used in antibiotics, vaccines, and vitamins d) By producing gases, such as carbon dioxide, which are used to make biofuels What describes the relationship of pathogens to virulence? a) Highly virulent pathogens almost always lead to a disease state when introduced to the body. b) Pathogens that cause an infection cannot also be virulent. c) Highly virulent pathogens are highly susceptible to the human immune system. d) Less virulent pathogens are less likely to lead to an infection. What is the key difference between a primary pathogen and an opportunistic pathogen? a) Primary pathogens can be fought off by the body's immune defense system, whereas opportunistic pathogens require synthetic interventions. b) Primary pathogens can infect certain people, whereas opportunistic pathogens can infect anyone. c) Primary pathogens can infect anyone, whereas opportunistic pathogens can cause disease if the host is immunocompromised. d) Primary pathogens are part of the human microbiome, whereas opportunistic pathogens are transmitted from another host. How can disease expression be described? a) Pathogens with high virulence tend to cause symptoms that include low-grade fevers or headaches. b) The infectious dose that is needed to cause illness is consistent from person to person. c) Virulent microorganisms result in the same form of disease in the host regardless of the route of transmission. d) Signs and symptoms associated with illness can be a result of many things, including an immune response What is the correct understanding of the median infectious dose? a) It is the number of pathogenic cells required to kill 50% of infected animals. b) It is the number of pathogenic cells required to cause active infection in 50% of inoculated animals. c) It is the amount of toxin required to see an immune response to infection in 50% of people. d) It is the amount of toxin required to infect 50% of the human population. Which structure aids in the evasion of phagocytosis by preventing immune cells from adhering to pathogens? a) Pili b) Fimbriae c) Peptidoglycan d) Capsule Which group contains a pathogen that adheres to host cells by using a large adhesive disc? a) Viruses b) Protozoans c) Fungi d) Bacteria Which phenomenon is found only in viruses? a) Antigenic drift b) Antigenic shift c) Mycotoxin production d) Capsule formation Which structure is used by certain bacteria to adhere to host tissues? a) Mycolic acid b) Glycoprotein gp120 c) Type 1 fimbrial adhesin d) M protein Which virulence factor aids in the adherence of bacterial pathogens to a host? a) Endotoxin b) Capsule c) O antigen d) Pili Which situation is an indirect result of endotoxin release? a) Phagocytes are recruited to the area. b) Inflammation and fever are initiated c) Host cells are lysed. d) Antiviral proteins are produced. Which characteristic is true of exotoxins? a) Exotoxins are produced by only gram-negative bacteria. b) Exotoxins are stable at high temperatures. c) Exotoxins are produced by only gram-positive bacteria. d) Exotoxins can cause cytokine storms. Which statement describes biofilms? a) Biofilms contain random collections of microorganisms. b) Biofilms are always pathogenic to the host. c) Biofilms form on fomites. d) Biofilms are highly structured communities. Which step in biofilm formation comes immediately after planktonic cells attach to a surface? a) Planktonic cells become sessile. b) Appendages and the extracellular polymeric substance interact. c) Sessile cells become planktonic. d) Planktonic cells colonize new areas. Which biofilms are produced by mutualistic microbes and are beneficial to a human host? a) Plaque biofilms that form on teeth b) Biofilms that line the intestinal mucosa c) Staphylococcus biofilms that form on urinary catheters d) Pseudomonas aeruginosa biofilms that form in the airway Why would bacteria living in a biofilm slow down their metabolism? Which type of microscopy allows the visualization of internal cellular structures in specially fixed microbial specimens? a) Differential interference contrast microscopy b) Fluorescence microscopy c) Brightfield microscopy d) Electron microscopy What does a phase-contrast microscope use to visualize a specimen? a) Fluorescence b) Light c) X-rays d) Electrons Which type of microscopy produces highly detailed three-dimensional images of a specimen? a) Transmission electron microscopy b) Scanning electron microscopy c) Phase-contrast microscopy d) Brightfield microscopy Which method of microscopy uses a laser to scan multiple planes and produces a three-dimensional image that can be used to visualize the internal structure of a biofilm? a) Transmission electron microscopy b) Brightfield microscopy c) Scanning electron microscopy d) Confocal microscopy