Reference no: EM131656399

1. Who was the first person to see the bacterial cells with the microscope?:

a. Louis Pasteur

b. Robert Koch

c. Antony van Leeuwenhoek

d. Robert Hooke

2. Some protists (protozoa)can cause diseases in animals and humans, which include :

a. Measles

b. Malaria

c. Polio

d. All of the above

3. Louise Pasteur developed vaccines for

a. Cholera, Small pox

b. Polio, tetanus

c. Influenza & Hepatitis

d. Anthrax & Rabies

4. Alexander Fleming discovered penicillin, from Penicillium, that killed bacterial pathogens causing diphtheria, scarlet fever, and gonorrhea.

a. True

b. False

5. What are Koch's postulates used for?

a. Directly relating a specific microbe to a specific disease

b. Identifying an unknown from a mixed culture of bacteria

c. Differentiating between Gram-negative and Gram-positive bacteria

d. All of the above

6. Robert Koch isolated which of the following organisms for the first time?

a. Staphylococcus

b. organism causing silkworm disease

c. Anthrax bacillus

d. Influenza virus

7. Main structural difference between prokaryotes and eukaryotes is:

a. Absence of cell wall in prokaryotes

b. Absence of a membrane that encloses DNA molecule or chromosome in prokaryotes

c. Absence of nucleic acid in prokaryotes

d. Absence of flagella in prokaryotes

8. Ribosomes are structures that manufactures proteins based on genetic instruction and are found:

a. in eukaryotes only

b. in prokaryotes only

c. both in eukaryotes and prokaryotes

d. in higher eukaryotes only

9. Under the microscope with Gram stain, gram positive bacteria will appear:

a. Blue-purple

b. Transparent

c. Green

d. Orange-red

10. Which of the following is NOT an organizational pattern common to all organisms?

a. Genetic organization

b. Protein synthesis

c. Compartmentation

d. Endomembrane system

11. A light microscope usually has at least three objective lenses and they magnify an object:

a. 5, 50, and 75 times

b. 20, 100, and 200 times

c. 10, 40, and 100 times

d. 100, 200, and 500 times

12. Gram staining technique differentiates bacterial cells into two group.

a. True

b. False

13. The instrument most widely used to observe microorganisms is the light microscope.

a. True

b. False

14. Which of the following statement is true for Archaea?

a. They contain peptidoglycan in their cell wall

b. They are eukaryotes living in extreme environments

c. They are prokaryotes living in extreme environments

d. They consist of major human pathogens

15. Which of the following is an important function of bacterial capsule?

a. to protect against the phagocytes

b. house the enzymes required for bacterial metabolism

c. give rigidity to the cell

d. To control flow of nutrients into the cell.

16. Main locomotor organ of a bacterium is

a. Pilus

b. Fimbria

c. Flagellum

d. Protoplasm

17. Which of the following structures are used by bacteria to adhere (stick to) the surfaces?

a. Cell membrane

b. Golgi apparatus

c. Pili

d. Flagella

18. What is the predominant component in a gram positive organism's cell wall?

a. Techoic acid

b. Lipoproteins

c. Lipopolysaccharide

d. Peptidoglycan

19. Which of the forms will be produced by some bacterial species under adverse conditions?

a. Reproductive form

b. Protoplast

c. Endospore

d. Cysts

20. In gram staining procedure, the gram negative bacterial cell wall loses crystal violet color because:

a. The peptidoglycan strand is thick

b. Teichoic acid is present

c. Peptidoglycan strands are absent

d. Peptidoglycan strands compose just single layer or two

21. Microbial growth progresses through distinct phases. In which phase all the bacterial population undergo binary fission?

a. The lag phase

b. The log or exponential phase

c. The stationary phase

d. The decline phase

22. Spore formation or sporulation is characteristics of:

a. gram negative bacteria

b.gram positive bacteria

c. Viruses

d. All of the above

23. Endospores are probably the most resistant living structure known :

a. True

b. False

24. A vacuum-sealed can of food is suitable for the development of botulism because it is oxygen free:

a. True

b. False

25. Culture media for growing microbes can be modified. A selective media inhibits the growth of certain microbes in a mixture while allow the growth of others :

a. True

b. False

26. The hereditary molecule DNA is organised as chromosomes. Chromosome:

a. is localized in the nucleus in all organisms

b. is always circular

c. is always present in the cytosol

d. exists as thread-like fiber, associated with proteins

27. Plasmids, present in many bacterial, archaeal, and fungal cells, are:

a. localized within chromosomes

b. extrachromosomal DNA

c. essential for normal survival of the cells

d. always linear structure

28. Copying mechanism for the genetic materials is called:

a. Transcription

b. Translation

c. Duplication

d. Replication

29. The information in a chromosome may be altered through a permanent change in a base sequence in the DNA and is called

a. Transcription

b. Translation

c. Replication

d. Mutation

30. Transposable elements (TEs) are segments of DNA those :

a. can move from one DNA site and integrate into another site

b. are referred to as "jumping genes"

c. may carry genes for antibiotic resistance

d. all of the above

31. Genes existing on plasmids may include those for:

a. capsule production

b. Krebs cycle enzymes

c. cell division

d. antibiotic resistance

32. The synthesis of an RNA molecule from a DNA molecule is called

a. replication

b. transcription

c. translation

d. DNA synthesis

33. Restriction endonucleases are enzymes that recognize and cut specific short stretches of DNA sequenceCloning in genetic engineering is defined as replicating bacteria to identical forms.

a. True

b. False

34. A bacterial cell undergoes binary fission and the daughter cells of the next generation contain the identical genes found in the parent. This is an example of:

a. Horizontal gene transfer

b. Vertical gene transfer

c. Transformation

d. Gene mutation

35. Bacteria reproduce using a type of cell division known as:

a. Meiosis I

b. Binary fission

c. Mitosis

d. Meiosis II

36. Conjugation is a recombination process in which:

a. Donor cell directly transfers plasmid DNA to recipient cell

b.genetic traits could be transferred if cell transfer occurred

c. F+ donor cell produces a conjugation pilus

d. All of the above

37. Transduction is the third form of horizontal gene transfer and involves virus:

a. True

b. False

38. When an organism infects the body without any detectable impairment of body function it is called:

a. Subclinical or inapparent infection

b. Acute infection

c. Chronic infection

d. Latent infection

39. If a 55 year old patient is suffering from infection of his right eye, what pattern of infection is seen?

a. Generalized infection

b. Focal infection

c. Localized infection

d. Congenital infection

40. If a patient had a bout of influenza and then suffered from pneumonia immediately, pneumonia would be called:

a. Biphasic illness

b. Systemic infection

c. Primary infection

d. Secondary infection

41. When the mother transmits an infection during pregnancy to the fetus is called:

a. Focal infection

b. Latent infection

c. Congenital infection

d. Systemic infection

42. When both parasite and host benefit from existence of the microbe in the body the host microbe relationship can be described as:

a. Commensalism

b. Symbiosis

c. Opportunistic Pathogenism

a. Opportunistic pathogen

d. Parasitism

43. Another term used for normal flora is:

a. Primary pathogen

b. Indigenous flora

c. Parasitic flora

44. If a very healthy athlete comes down with tuberculosis, what type of pathogen is Mycobacterium tuberculosis?

a. True (primary pathogen)

b. Secondary pathogen

c. Opportunistic pathogen

d. Congenital pathogen

45. Minimum number of organisms required to establish infection is called:

a. Pathogenic dose

b. Infectious dose

c. Virulence dose

d. Toxic dose

46. Which of the following virulence factors forms pore into white blood cells causing them to undergo lysis?

a. Hyaluronidase

b. Collagenase

c. Capsule

d. Leukocidin

47. Exotoxins are

a. heat sensitive

b. heat stable

c. very weak in their action

d. part of the bacterial cell wall

48. Exotoxins are

a. protein molecules

b. produced by gram positive and gram negative bacterial cells

c. released into the host environment

d. all of the above

49. Endotoxins are

a. heat stable

b. part of structural component in the outer membrane of gram-negative bacteria

c. released upon disintegration of gram-negative bacteria

d. all of the above

50. Successful invasiveness requires pathogens to have virulence factors which include

a. Enzymes

b. Exotoxins

c. Endotoxins

d. All of the above