Bacterial Pathogenesis 7

Previous exams & Formative:

1- All the following are characters of carriers Except: a. They are not confined to bed b. They carry the pathogenic organism in the inter-epidemic periods c. They communicate with public without being noticed d. They have symptoms of disease

2- Endotoxin produced by gram negative bacteria is present in a. Peptidoglycan b. Lipopolysaccharide (Lipid A) c. Teichoic acid d. Inner membrane

3- Mediate adherence to epithelial surfaces: a. Capsule b. Ordinary pili c. Glycocalyx d. Sex pili e. Cell wall a. Cell wall b. Cell membrane c. Pili d. Flagella a. Endotoxins are secreted from cells b. Cause of endotoxins shock c. Produced by gram negative microorganisms d. Can cause fever a. Flagellum b. Plasmid c. Peptidoglycan d. Glycocalyx a. Infectious Dose b. Pathogen c. Pathogenesis d. Disease a. Connective tissue b. Nails c. Collagen d. All of the above a. Fimbriae b. Capsule c. Slime layer d. Both a & c

4- Which part of a microbial cells causes an endotoxin?

5- Which of the following is not true related to endotoxins?

6- Which of the following is the most important structure related to microbial attachment to cells?

7- What is defined as the number of microbes required to produce a disease?

8- Hyaluronidase causes damage to which of the following?

9- Which of the following is considered an adherence factor?

6- d 7-a 8-a 9- d

Extra: a. It acts as a spreading factor b. It promotes blood clotting. c. It is an example of an adhesin d. It is produced by immune cells to target pathogens.

1- Which of the following applies to hyaluronidase?

2- The most important virulence factors are: a. Adhesions b. Invasiveness c. Toxigenicity d. Enzymes e. All of the above a. Hyaluronidase b. Coagulase c. Catalase d. DNase

3- Which is the following enzyme acts as a spreading factor?

4- The bacterial pili mainly contain: a. Carbohydrates b. Lipids c. Proteins (pilins)

5- Toxoid is: a. Toxin lost its toxicity but still antigenic b. Toxin lost its toxicity and antigenicity c. Toxin lost its antigenicity but not toxicity d. Toxin lethal in very minimal dose e. Toxin lethal to bacteria

6- The exotoxins are usually: a. Thermolabile b. Thermostable c. Not affected by formalin d. Neurotoxins e. Enterotoxins

7- The ability of a pathogen to spread in the host tissues after establishing the infection is known as a. Adhesion b. Invasiveness c. Toxigenicity d. None of these

8- A toxic material within the bacterial cell, non -diffusible usually lipopolysaccharideprotein complex, heat and formalin stable and poorly antigenic. This material is: a. Endopigment b. Endotoxin c. Endogenous pyrogen d. Exotoxin e. B & C are correct

9- All of the following are characters of endotoxin EXCEPT: a. Heat stable b. Polysaccharide lipid complex c. Action is often enzymatic d. Produced by gram negative bacteria e. Poorly immunogenic a. Streptococcus pyogenes b. Staphylococcus aureus c. Staphylococcus epidermidis d. Staphylococcus saprophyticus e. Streptococcus agalactiae

10- Coagulase enzyme is able to accelerate the formation of fibrin cl from its precursor fibrinogen. It is considered an important virulent factor for bacteria. Which bacterial species can produce it?

11- Exotoxin have all of the following characters EXCEPT: a. Enzymatic action b. Specific tissue affinity c. Active in minute dose d. Polysaccharide lipid in nature e. Strong immunogen

12- The role of bacterial capsules as virulence factors is usually related to their ability to interfere with: a. Antibody binding b. B lymphocyte activation c. Antibacterial penetration of bacterial cells d. Phagocytosis e. The release of interferon-gamma and other macrophage activating cytokines

13- Carriers constitute an important source of infection. The following is CORRECT regarding carriers: a. They carry pathogenic organisms but have mild symptoms b. They carry pathogenic organisms only for short periods c. They are apparently healthy d. They cannot transmit pathogenic organisms to others e. They transmit infections to others only during epidemics

14- A quantitative measure for pathogenicity is known as: a. True pathogenicity b. Virulence c. Transmissibility d. Toxicity e. Reproducibility

15- All the following is correct regarding opportunistic pathogens EXCEPT: a. Frequently cause infection in healthy subjects b. Cause infection in immunocompromised patients c. Are usually members of normal flora d. Known as potential pathogens e. Are not true pathogens

16- Virulence of an organism is a quantitative measure for pathogenicity. All the following is correct with regard to virulence EXCEPT: a. Measured by the number of organisms required to cause disease b. Expression could be regulated by environmental factors c. Cannot be transmitted between bacteria d. Genes could be plasmid or phage encoded e. Genes are usually aggregated in pathogenicity associated islands

17- Invasiveness of bacteria could be facilitated by: a. Coagulase enzyme b. Collagenase enzyme c. Catalase enzyme d. Urease enzyme e. Exotoxin with enzymatic activity

18- Which one of the following microbial structures has anti-phagocytic action? Select one: a. Spores b. Capsule c. Cell wall d. Flagella

19- Pathogens that can cause serious infections in immunocompromised patients are called Select one: a. Infectious pathogens b. Lethal pathogens c. Virulent pathogens d. Opportunistic pathogens a. Invasion, infection, adhesion, exposure b. Adhesion, exposure, infection, invasion c. Exposure, adhesion, invasion, infection d. Disease, infection, exposure, invasion a. A surface protein allowing the pathogen to bind to host cells b. A secondary host the pathogen can infect c. A surface protein the host immune system recognizes d. The ability to form a provirus a. It acts as a spreading factor. b. It promotes blood clotting. c. It is an example of an adhesin. d. It is produced by immune cells to target pathogens. a. Degrade antibodies b. Promote pathogen spread through connective tissue. c. Degrade nucleic acid to promote spread of pathogen d. Degrade cell membranes to allow pathogens to escape phagosomes

20- Which of the following choices lists the steps of pathogenesis in the correct order?

21- Which of the following would be a virulence factor of a pathogen?

22- Which of the following applies to hyaluronidase?

23- Phospholipases are enzymes that do which of the following?