MCQOPTIONS
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MCQOPTIONS
This section includes 229 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Transfection involves the introduction of plasmid hybrid DNA into the host cell. |
| A. | True |
| B. | False |
| Answer» C. | |
| 2. |
Which of the following enzymes cut the DNA molecule at a particular nucleotide sequence? |
| A. | restriction endonuclease |
| B. | exonuclease |
| C. | ligase |
| D. | polymerase |
| Answer» B. exonuclease | |
| 3. |
A chemical agent that kills the microorganisms and is commonly applied to substances used on inanimate objects are _______________ |
| A. | Antiseptics |
| B. | Sanitizer |
| C. | Disinfectants |
| D. | Antibiotics |
| Answer» D. Antibiotics | |
| 4. |
If a canning procedure is not properly followed, which type of microbe is most likely to grow in the canned food? |
| A. | Obligate Aerobe |
| B. | Acidophile |
| C. | Mesophile |
| D. | Obligate Anaerobe |
| Answer» E. | |
| 5. |
Which of the following agent is used to disinfect skin? |
| A. | Chlorine |
| B. | Formaldehyde |
| C. | Quaternaries |
| D. | Ethylene oxide |
| Answer» D. Ethylene oxide | |
| 6. |
The oldest eukaryotic organisms are considered to be |
| A. | diplomonads like Giardia |
| B. | archaea |
| C. | fungi |
| D. | animals |
| Answer» C. fungi | |
| 7. |
Genetic and biochemical similarities between contemporary cyanobacteria and eukaryotic chloroplasts are accepted to mean that |
| A. | eukaryotes evolved from bacteria |
| B. | eukaryotes evolved from archaea |
| C. | oxygenic photosynthesis first evolved in eukaryotes |
| D. | cyanobacteria arose from chloroplasts which escaped from plant cells |
| Answer» C. oxygenic photosynthesis first evolved in eukaryotes | |
| 8. |
All membranes of free-living organisms have phospholipid bilayers, but exception is |
| A. | bacteria |
| B. | fungi |
| C. | archaea |
| D. | protozoa |
| Answer» D. protozoa | |
| 9. |
Among the following which one is the most effective method of killing microorganisms? |
| A. | High temperature |
| B. | Low temperature |
| C. | High temperature,high moisture |
| D. | Low temperature,high moisture |
| Answer» D. Low temperature,high moisture | |
| 10. |
If a 1:600 dilution of a test compound kills a standard population of Staphylococcus aureus in 10 minutes but not 5 minutes while a 1:60 dilution of phenol kills the population in the same time, what is the phenol coefficient of the test compound? |
| A. | 1 |
| B. | 5 |
| C. | 10 |
| D. | 50 |
| Answer» D. 50 | |
| 11. |
The process of making an object free from living organisms including bacterial and fungal spores and viruses is known as |
| A. | pasteurization |
| B. | antisepsis |
| C. | disinfection |
| D. | sterilization |
| Answer» E. | |
| 12. |
We require less time to kill the population of many cells. |
| A. | True |
| B. | False |
| C. | May be |
| D. | Can't say |
| Answer» C. May be | |
| 13. |
How much time is required by the young cells to be killed by a lethal agent? |
| A. | 24 hours |
| B. | 3-4 hours |
| C. | 30 mins |
| D. | 5 mins |
| Answer» D. 5 mins | |
| 14. |
The time required to kill 90% of the microorganisms in a sample at a specific temperature is the |
| A. | decimal reduction time |
| B. | thermal death point |
| C. | F value |
| D. | D value |
| Answer» E. | |
| 15. |
Which of the following conditions are required for determination of thermal death time? |
| A. | temperature is varied |
| B. | time is fixed |
| C. | temperature is fixed and time is varied |
| D. | temperature is fixed and time is not selected |
| Answer» D. temperature is fixed and time is not selected | |
| 16. |
Various bacterial species can be subdivided into |
| A. | subspecies |
| B. | biovarieties |
| C. | serovarieties |
| D. | all of these |
| Answer» E. | |
| 17. |
One drawback to the use of ultraviolet light as a sterilizing agent is its |
| A. | failure to kill bacteria |
| B. | failure to bacterial spores |
| C. | failure to kill microbes in a closed environment |
| D. | failure to kill microbes located in the center of an object |
| Answer» E. | |
| 18. |
Which of the following microorganisms is classified as a member of archaebacteria? |
| A. | Gyanobacteria |
| B. | Methanobacteria |
| C. | Trichomonads |
| D. | Mycoplasma |
| Answer» C. Trichomonads | |
| 19. |
In microbiology, Prion is not |
| A. | living cell |
| B. | heat resistant |
| C. | found in man |
| D. | single cell protein |
| Answer» B. heat resistant | |
| 20. |
Which disinfectant was the most effective against Salmonella"? |
| A. | Phenol |
| B. | Cetylpyridinium chloride |
| C. | Hexachlorophene |
| D. | Merthiolate |
| Answer» E. | |
| 21. |
Eukaryotic micro organisms include |
| A. | protozoa |
| B. | fungi |
| C. | algae |
| D. | all of these |
| Answer» E. | |
| 22. |
Archeal cells usually do not contain peptidoglycan, rather contain pseudo-peptidoglycan which is mainly composed of |
| A. | N-acetylmuramic acid and L-amino acids |
| B. | N-acetylmuramic acid and D-amino acids |
| C. | N-acetyltalosaminuronic acid and D-amino acids |
| D. | N-acetyltalosaminuronic acid and L-amino acids |
| Answer» E. | |
| 23. |
Solutions of sodium hypochlorite of a 1% concentration are used for ________ |
| A. | sanitizing dairy equipments |
| B. | personal hygiene and a household disinfectant |
| C. | household bleaches |
| D. | disinfecting open wounds |
| Answer» C. household bleaches | |
| 24. |
The phospholipids present in cytoplasm membrane of eubacteria is mainly |
| A. | phosphoglycerides |
| B. | polyisoprenoid |
| C. | phospholipoprotein |
| D. | none of these |
| Answer» B. polyisoprenoid | |
| 25. |
Which of the following is not true for eukaryotic cells? |
| A. | Nucleus is bounded by nuclear membrane |
| B. | Chromosomes contain histones |
| C. | Chloroplasts and mitochondria contains 70S ribosomes |
| D. | Gas vacuoles are present |
| Answer» E. | |
| 26. |
Polyvinylpyrrolidone (PVP) is a complex belonging to which group? |
| A. | Phenolic compounds |
| B. | Iodophors |
| C. | Metals |
| D. | Aldehyde |
| Answer» C. Metals | |
| 27. |
In the three domain system of classification, the traditional bacteria are placed in the |
| A. | eukarya |
| B. | archaea |
| C. | eubacteria |
| D. | none of these |
| Answer» D. none of these | |
| 28. |
Which of the following is sterilized with the help of glutaraldehyde? |
| A. | Thermometers |
| B. | Bronchoscopes |
| C. | Cystoscopes |
| D. | All of these |
| Answer» E. | |
| 29. |
A high concentration of which of the following compounds in the material generally increases the thermal resistance of microorganisms? |
| A. | proteins |
| B. | carbohydrates |
| C. | lipids |
| D. | salts |
| Answer» C. lipids | |
| 30. |
Alcohol concentrations above 60% are effective against _________________ |
| A. | bacteria |
| B. | fungi |
| C. | germs |
| D. | viruses |
| Answer» E. | |
| 31. |
Micro organisms are found in which of the following kingdom of five kingdom concept (Whittaker's classification)? |
| A. | Monera |
| B. | Protista |
| C. | Fungi |
| D. | All of these |
| Answer» E. | |
| 32. |
The unifying feature of the archaea that distinguishes them from the bacteria is |
| A. | habitats which are extreme environments with regard to acidity |
| B. | absence of a nuclear membrane temperature |
| C. | presence of a cell wall containing a characteristic outer membrane |
| D. | cytoplasmic ribosomes that are 70S |
| Answer» C. presence of a cell wall containing a characteristic outer membrane | |
| 33. |
Which of the following is best to sterilize heat labile solutions? |
| A. | Dry heat |
| B. | Autoclave |
| C. | Membrane filtration |
| D. | Pasteurization |
| Answer» D. Pasteurization | |
| 34. |
Which of the following is not true for prokaryotic organism? |
| A. | Nucleus is not bounded by nuclear membrane |
| B. | Chromosomes does not contain histones |
| C. | 80S ribosomes are distributed in cytoplasm |
| D. | Cell wall contains peptidoglycan as one of the major component |
| Answer» D. Cell wall contains peptidoglycan as one of the major component | |
| 35. |
Some amount of air is also essential inside the chamber of the autoclave. |
| A. | True |
| B. | False |
| C. | May be |
| D. | Can't say |
| Answer» C. May be | |
| 36. |
What are Blue-Green bacteria called? |
| A. | Acquaobacteria |
| B. | Cyanobacteria |
| C. | Protozoa |
| D. | None of the above |
| Answer» C. Protozoa | |
| 37. |
Evolutionary relationships between groups of organisms are determined using which of the following type of information? |
| A. | Comparisons of nucleotide sequences |
| B. | Comparisons of biochemical pathways |
| C. | Comparisons of structural features |
| D. | All of the above |
| Answer» E. | |
| 38. |
Which of the following agents are used as a preservative in ophthalmic solutions? |
| A. | alcohol |
| B. | quaternary ammonium salts |
| C. | phenol |
| D. | aldehydes |
| Answer» C. phenol | |
| 39. |
Vegetative cells are much more sensitive to heat than are spores. |
| A. | True |
| B. | False |
| C. | May be |
| D. | Can't say |
| Answer» B. False | |
| 40. |
Which of the following may account for the small size of the cells? |
| A. | The rate of diffusion |
| B. | The surface area/volume ratio |
| C. | The number of mRNAs that can be produced by the nucleus |
| D. | All of the above |
| Answer» E. | |
| 41. |
One of the reasons for the evolutionary success of the kingdom Monera is that its members are nutritionally diverse. Which of the following(s) is/are the way(s) of obtaining energy? |
| A. | Photoautotrophy |
| B. | Photoheterotrophy |
| C. | Chemoheterotrophy |
| D. | All of the above |
| Answer» E. | |
| 42. |
Living organisms have many complex characteristics. Which one of the following is shared by non-living matter as well? |
| A. | Homeostasis |
| B. | Tissues |
| C. | Reproduction |
| D. | Molecules |
| Answer» E. | |
| 43. |
Passage of water from a low solute concentration into the cell is referred to as ______________ |
| A. | plasmoptysis |
| B. | plasmolysis |
| C. | isotonic |
| D. | hypertonic |
| Answer» B. plasmolysis | |
| 44. |
The five-kingdom system of classification was set up by |
| A. | Louis Pasteur |
| B. | Robert Whittaker |
| C. | Robert Koch |
| D. | Masaki Ogata |
| Answer» C. Robert Koch | |
| 45. |
Escherichia coli is much more resistant to cationic disinfectants than Staphylococcus aureus. |
| A. | True |
| B. | False |
| C. | May be |
| D. | Can't say |
| Answer» B. False | |
| 46. |
Mycoplasmas are different from the other prokaryotes by |
| A. | presence of chitin in cell walls |
| B. | presence of murrain in cell walls |
| C. | presence of proteins in cell walls |
| D. | absence of cell wall itself |
| Answer» E. | |
| 47. |
Which of the following material is sterilized by use of red heat? |
| A. | Soiled dressings |
| B. | Inoculating wires and loops |
| C. | Glass slides |
| D. | All-glass syringes |
| Answer» C. Glass slides | |
| 48. |
The binomial name of a microbe is composed of |
| A. | its kingdom and genus names |
| B. | its genus name and a species modifier |
| C. | its family and class names |
| D. | its genus and species names |
| Answer» C. its family and class names | |
| 49. |
What is Mycology? |
| A. | Study of viruses |
| B. | Study of nucleic acid |
| C. | Study of bacteria |
| D. | Study of fungi |
| Answer» E. | |
| 50. |
Carl Woese and his colleague are best known for establishing |
| A. | the five kingdom system |
| B. | the three domain system |
| C. | the prokaryote-eukaryote system |
| D. | the plant-animal system |
| Answer» C. the prokaryote-eukaryote system | |