MB C1 Self Quiz

taddio's version from 2010-08-12 20:17


Self Quiz 1
Question Answer
1. (t/f)Less than 1% of microorganisms are harmful and cause diseaseTrue
2. (t/f)Life on earth would be much better if all microbes were eradicatedFalse
3. Which of the following is not trueMicrobes can only be found where man naturally habituates
4. Which of the folowing is not a reason for microorganisms being useful in researchMicrobes are easily controlled


5. Why are microbes important to study and how are they directly useful to man? They are important to study because of their relation to human health (the diseases they produce).Some are directly useful for their production of antibiotics ,digestive enzymes in ruminants (breakdown of cellulose) and in the food industry (mushrooms...pickles...sauerkraut...yogurt...dairy and bread).Microbes are important to the human environment being the first and the last links in the complex web of life (photosynthetic chemosynthetic microbes are able tp respectively capture the sun's or mineral's energy utilizing it to make molecules that can be used by other organisms as food when they ingest them).Microbes are also responsible for the decompisition of dead organic matter returning minerals and inorganic matter to the soil for plants to use in making protoplasm.In turn man can eat these plants directly or indirectly by eating the herbivores(plant eaters) who feed on them. Some microbes are also beneficial to man in that they can degrade industrial waste products into less toxic and harmless chemicals. Microbes are invaluable study subjects because of their versatiliy inr esearch (being able to be genetically engineered to products useful to man such as insulin and human growth hormone).The study of microbes also give us insight into the life processes in all life forms.


Question Answer
6. (t/f)People in central Asia are still sufferring from smallpox infectionsFalse
7. AlgaePhotosyntheic large cells that rarely cause human disease
Bacteriasingle-celled non-nucleated microorganisms
Fungimulticellular nucleated microorganism that has branching filaments
Protozoalarge single-celled non-nucleated microorganisms
Virusesacellular entities that require a host for multiplication
Helminthesparasitic worms


Question Answer
8. (t/f)Animals such as worms and ticks are too large to be included in a microbiology courseFalse.Worms have microscopic stages in their life cycles that can cause disease and the arthropods (as represented by the tick) can transmit these stages as well as other disease-causing microbes.
9. What is the difference between etiology and epidemiologyEtiology is the assignment or study of causes and origins of a disease. Epidiomology is the study of factors and mechanisms involved in the spread of disease within a population.
10. The epidemic that infected Europe,North Africa and the Middle East and killed tens of millions was known as the Black Death.The disease was caused byBubonic plague


Question Answer
11. Which of the following people in history did not make a contribution toward preventive medicine by stricter sanitation practicesAngelina Hasse
12. The event that triggered the development and establishment of microbiology as a science is theDevelopment of the microscope
13. What was Leeuwehoek"s contribution to microbiologyThe development of high-quality lenses by Leeuwenhoek made it possible to observe microorganisms and later to formulate the cell theory.
14. Which scientist first disproved spontaneous generation by showing that maggots only appear on decaying meat that has been exposed to fliesRedi
15. Which of he following experiments was not useful in disproving "spontaneous generation"Louis Pasteur's "pasteurization process" in wine making


Question Answer
16. The biggest obstacle in the acceptance and development of the science of microbiology wasTheory of spontaneous generation
17. Besides providing strong evidence toward the disproof of spontaneous generation,Loius Pasteur made many other contributions toward the advancement of microbiology.Which of the following is not one of Pasteur's contributionsDeveloped a cowpox vaccine for smallpox
18. The germ theory of disease states thatMicroorganisms that invade other organisms can cause disease in those organisms
19. Put Koch's postulates in orderc(1)The specific causative agent must be found in every case of the disease a(2)The disease organism must be isolated in pure culture d(3)Inoculation of a sample of the culture into a healthy susceptible animal must produce the same disease b(4)The disease organism must be recovered from the inoculated animal
20. What did Semmelweis and Lister contribute to microbiologyLister and Semmelweiss contributed to improved sanitation in medicine by applying the germ theory and using aseptic technique


Question Answer
21. MetchinikoffImmunology... cellular immunity(phagocytes)
BeijerinckVirology...infectious filtrates contain viruses ("jumping") genes
EhrlichChemotherapy...salvarsan against syphilis


Question Answer
22. Describe the contributions of the folowing scientists to the field of microbiology:Beijerinck...Fleming... and MetchinikoffBeijerinck was the first to characterize viruses.Fleming discovered penicillin.Metchinikoff identified the role of phagocytosis in immune defenses.
23. (a)How do bacteria differ from viruses (b)are there ways to fight infectious diseases caused by bacteria other than through the use of antibiotics(a)Viruses are smaller than bacteria. Viruses are considered to be on the "borderline" of the living and non-living;bacteria are living. Viruses are cellular...bacteria acellular. (b)As early as the 1920s bacteriophage therapy which employs the use of certain viruses that attack and kill specific bacteria has been successfully used to fight disease-causing bacteria
24. (t/f)Scientists have found many antibiotics by examining microorganisms in soilTrue


Question Answer
25. James Watson and Francis CrickDiscovered the alpha helical structure of DNA
Reed and colleaguesIdentified the virus that caused yellow fever
Avery,McCarty and McLeodProved that DNA was responsible for acquiring new changes
Beadle and TatumUsed mold to demonstrate how genetic information controls metabolism
Selman WaksmanDiscovered and isolated the antibiotic streptomycin in 1943
Frederick GriffithDiscovered that live harmless bacteria could become disease-causing by acquiring heritable traits from dead ones


Question Answer
26. Use the following diagram to explain how Pasteur's swan-necked flasks prevent contamination of sterile broth in the flasks.Describe what happens to the sterile broth in (a) after it has been allowed to cool as in (b).What happens to the broth after the flask has been tipped enough to let the broth come in contact with the dust and microorganisms and is tipped back as in (c)(a)Heating the broth and the neck of the flask to boiling would kill all the vegetative cells.(note:had resistance endospores of bacteria been present in the broth the boiling would not have destroyed them) Boiling also forced out any remaining air thus removing any dust-laden bacteria. (b)Cooling the broth slowly allowed air to return to the flask.The swan-neck bend in the flask traped any bacteria and dust that would have entered had the neck been straight.The broth thus remains free of microbial growth.(c)Tipping of the flask allowed some of the sterile broth to contact the dust and the microbes present in the bend of the neck. Returning the flask upright allowed the contamination to reach the broth in the flask and recontaminate the flask.