Microbiology Midterm Exam

Micro exam #3 1. Which of the following is an important component of the epithetical cell defense mechanisms in the respiratory tract? a. keratin b. dermis c. ciliated epithelial cell d. all of the above e. none of the above 2. Besides the mechanical structure of the skin, which of the following is an important protection against microorganisms on the skin? a. oil secretion of the sebaceous gland b. organic acids in sweat c. acidic secretions d. all of the above e. none of the above 3. Which is the most abundant wandering phagocyte? a.basophil b.eosinophil c.monocytes d.lymphocyte e.neutrophil 4. Which of the following pairs are mismatched? a. animals: usually diploid b. fungi: usually diploid c. protozoa: usually diploid d. algae: usually hapiod e. plants: usually diploid 5. the complement system is involved with all of the following expect: a. opsonization b. chemotaxis c. Production of antibodies d. triggering of fever 6, 7 ,8, 9, 10, 11 12. ___________ Specificity and memory are associated with body defense mechanism a. Inflammatory response phagocytosis by macrophages and neutrophils c. interferon d. T cell and b cell responses e. anatomical behaviors in the body

13. Which of the following is found in the greatest concentration in the serum? a. IgA b. IgG c.IgM d. IgD e.IgE 14. A bacterial cell coated with the complement c3b is prepared for: a. lysis by holes in the cell membrane b. phagocytosis by phagocytes c. replication via conjugation d. elimination by cytoplasmic T cells 15. which of the following characteristics is shared by the skin and the mucous membranes? a. they both are constantly shedding and replacing cells b. they both have cilia c. the outer layers are composed of dead cells d. sebum may be present 16. Which of the following must be present for a T cell to recognize an antigen? a. b cell b. cytokinesis c. antibodies d .histocompatibility antibodies e. platelets 17.cyotoxic c cells recognize which of the following? a. virus- infected cell b. tumor cells c. surgical implants d. all of the above e. none of the above 18. helper t cells influence which of the following with lymphokines? a. b cells b. other t cells c. the same t cell that produces them d. all of the above e. none of the above 19. Acquired immunity is most beneficial because it provides a. immediate responses to all invaders b. specific responses geared to specific invaders c. passive barrier protection against all invaders

d. none of the above 20. How does apirin act to decrease the symptoms of inflammation? a. it acts as a anti-prostaglandin b. it is an antioxoid for most microbial toxins c. it prevents complement activation d.it interferes with the actions of interfereons 21. all of the following are events of early inflammation except A. B. C. D.

macrophages appear first and begin phagocytosis. 
 hemical mediators and cytokines are released. 
 brief vasoconstriction is followed by vasodilation. 
 exudate and pus can accumulate.

22. Which of the following pairs is mismatched? a. entamoeba: pseudopodia b. euglena: flagellum c. plasmodium: merozoites d. paramecium: two nuclei e. toxoplasma: cilia 23. salivia contributes to the first line of defense against infection by a. washing microbes from teeth b. destroying microbes through the action of lysozyme c. presenting a barrier to adhesion d. both a and b 24. MACS are: a. the initial trigger for the classical compliment system. b.the initial trigger for the alternate compliment system c. the initial trigger for the ? compliment system d. the initial trigger for the classical and alternate compliment system e. the end result of only the alternate compliment system 25. which of the following are involved in microbial antagonism? a. gram negatives only b. overgrowth of fungi c. staphylococci present on skin d. Neisseria bacteria 26. an organism that is normally associated with the body without causing disease but can cause if certain conditions change is a. pathogenicy b. virulence c. opportunist

d. infectious e.none of the above 27. Which of the following choices shows the order in which WBC migrate to infected tissues? a. macrophages- monocytes b. lymphocytes- macrophages c. neutrophils- macrophages d. neutrophils- monocytes e. macrophages- neutrophils 28. antigens are: a. specific molecules that the body recognizes as foreign b. protiens that the body produces against invaders c. cells that protect the body against invaders d. protiens on the surface of our cells that pathogens attach to e. enzymes secret to destroy a pathogens wall 29. Plankton is composed of which of the following types of eukaryotic microbes? a. fungi b. algae c. protozoa d. both algae and protozoa e. both fungi and algae 30. Conjugation is a reproductive process associated with which of the following types of protozoa? a. ciliates b. amoebae c. dinoflagella d. kintetophplastids 31. Which of the following is NOT a defining characteristic of protozoa? a. they all have a eukaryotic cellular structure b. they are all unicellular c. they lack cell walls d.they are all motile though different types of motility differ among different groups 32. Most of the fungi that spoil food belong to the divison: a. basiddiomycota b. deuteromyocytes c. zygomycota d. Ascomycota

33. Lichens are composed of which of a symbiosis of fungi and which of the following? a. green algae b. cyanobacteria c. euglenoids d. cyanobacteria or green algae e. euglenoids or dinogflagella 34. which of the following statements concerning viruses is false? a. viruses never contain both DNA and RNA b. viruses enter a cell to complete replication they have begun extracellulary c. some viruses have an outer membrane called an envelope d. viral capsids can assume one of three basic shapes e. tobacco mosaic viruses was the first virus to be discovered and characterized 35.viruses are primarily classified according to their A) type of nucleic acid. B) type of life cycle. C) number of chromosomes. D) shape. 36. host specificity of a virus is due to: A) particular genes that it shares with the infected cell. B) the presence of an envelope. C) differences in size between the virus and the host cell. D) the presence or absence of a cell wall on the host cell. E) interactions between viral and cellular surface molecules. 37.How are prions different from all other known infectious agents? A) They cannot reproduce outside a cell. B) They act as slow viruses. C) They cause neurological problems. D) They can be destroyed by incineration. E) They lack nucleic acid 38. Which of the following infectious particles do NOT have protein in their structure? A) bacteriophages B) prions C) animal viruses D) viroids E) both prions and viroids 39. Viroids infect

A) bacteria. B) plants. C) fungi. D) plants and animals. E) all organisms 40. Reverse transcriptase is associated with which of the following? A. dsDNA viruses b.+ssRNA viruses c.-ssRNA viruses d. retroviruses 41. Which of the following situations might cause normal microbial to become opportunistic pathogens? a. growth on the surface of intact skin b. growth of microorganisms on the excreted cellular ? and dead cells in the larger intestine c. treatment of cancer patient with radiation d. growth of lactabacillus on the surface of teeth 42. A protozoan and its resident bacteria invade the body of a worm The bacteria release toxins and exoenzymes that immobilize and digest the worm, and the protozoan and bacteria absorb the nutrients produced. The relationship between the protozoan and the bacteria would best be described as A) commensalism. B) mutualism. C) parasitism. D) both commensalism and parasitism. E) a nonsymbiotic relationship. 43. Which of the following is considered part of the indigenous microbiota of the female reproductive system? A) Candida B) Lactobacillus C) E. coli D) Bacteroides E) both Candida and Lactobacillus ( sopposed to be this but its not even on the test. If its NOT the answer is C. E.COLI) 44) Among the virulence factors produced by Staphylococcus aureus are hemolysin, coagulase, hyaluronidase, and enterotoxin. Which of these factors contribute(s) to the ability of S. aureus to invade the body? A) coagulase B) enterotoxin C) hemolysin (person picked this)

D) hyaluronidase (online it says D) 45. which of the following is incorrect about the compliment system? a. composed of at least 26 blood proteins b.its components only appear in the blood during a response to a pathogen c.acts as a cascade reaction d.may involve classical pathway e. may involve alternate pathway 46. A nosocomial disease is a disease acquired A) by being bitten by an infected insect. B) by eating contaminated food. C) by using a contaminated needle. D) in a health care facility. E) by having unprotected sexual intercourse 47. correct sequence of disease process: d.incubation,prodromal,invasive,decline,convalescence 48. name the 2 portals of entry for neisseria menigitids: mouth nose 49. A, B, OR C 50. Which of the following is an example of an exotoxin? A) neurotoxins B) coagulase C) lipid A D) streptokinase E) collagenase 51. In which of the following do the mucous membranes serve as a portal of entry for disease? A) A pathogen crosses from the mother to the fetus by way of the placenta. B) A pathogen is introduced into the body when the person rubs the eye with contaminated fingers and the pathogen is washed into the nasal cavity by way of tears. C) A person is bitten by a mosquito that carries the malaria parasite. D) Fungi digest the outer layer of the skin. E) A person receives an injection with a contaminated needle. 52. Which of the following statements concerning B cell receptors is false? A) They are formed in response to an encounter with an antigen.

B) They are complementary in shape to a specific antigenic determinant that they may or may not encounter. C) They are bound to the surface of B lymphocytes and have two antigen-binding sites. D) Each B lymphocyte is randomly generated with antibody variable regions that determine its BCR. E) Scientists estimate that each person forms at least 1011 different types of B lymphocytes with distinct BCRs. 53. What protozoan stage allows for transmission of intestinal parasites from one host to another? a. cysts b.mermozoite c.schizont d.foraminifera e.kinetoplast 54. The primary natural habitat of a pathogen where it continues to exist is called the a. fomite b. carrier c. vector d. resevior e. source