Download Dr. Raj Ramakrishnan, Ph.D. Concept Questions Read the chapter

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Dr. Raj Ramakrishnan, Ph.D.
Concept Questions
Read the chapter materials. Take some time to write answers to these questions. If you can answer
them, you have a good grasp of the material! Good luck!
DISCLAIMER: Concept questions provide only general guidelines as to material which the student is
assigned to learn. They are not contractual upon the instructor as to content or appearance of
material on the examination, by weight or by difficulty.
Chapter 1
1. Identify the groups of microorganisms included in the scope of microbiology, and explain the criteria
for including these groups in the field.
2. Why was the abandonment of the spontaneous generation theory so significant?
3. Using the scientific method, describe the steps you would take to test the theory of spontaneous
generation. What are variables and controls?
4. Explain how inductive and deductive reasoning are similar and different.
5. Where do you suppose the "new" infectious diseases come from?
6. Add up the numbers of deaths worldwide from infectious diseases (Fig 1.4). Look up each disease in
the index and see which ones could be prevented by vaccines or treated with drugs. How many do you
think could have been prevented by modern medicine?
7. What events, discoveries, or inventions were probably the most significant in the development of
microbiology?
8. Construct the scientific name of a newly discovered species of bacterium, using your name, a pet's
name, a place or a unique characteristic. Be sure to use proper notation and endings.
Chapter 2
This material can appear in all chapters on all exams. I expect my students to know the basic chemistry
contained in this chapter without the necessity of any review in this course. Unfamiliarity with this
material in a "2000 level" science course is a serious deficiency!!!
Chapter 3
1. Explain what is involved in isolating microorganisms and why it is necessary to do this.
2. Compare and contrast two common laboratory techniques for separating bacteria in a mixed
sample.
3. Briefly explain how an image is made and magnified.
4. How can one obtain 2000X magnification with a 100X objective?
5. Differentiate among the ingredients and functions of enriched, selective, and differential media.
6. What kind of medium might you make to selectively grow a bacterium that lives in the ocean?
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Dr. Raj Ramakrishnan, Ph.D.
7. What kind of medium might you make to selectively grow a bacterium that lives in the human
stomach?
Chapter 4
1. Name several general characteristics that could be used to define the prokaryotes. What does it
mean to say that bacteria are ubiquitous? In what habitats are they found?
2. Describe the structure of a flagellum and how it operates. What are the four main types of flagellar
arrangement? How does the flagellum dictate the behavior of a motile bacterium? Differentiate
between flagella and periplasmic flagella. List some direct and indirect ways that one can determine
bacterial motility.
3. List the components of the cell envelope. Explain the position of the glycocalyx. What are the
functions of slime layers and capsules? How is the presence of a slime layer evident even at the level of
a colony?
4. Differentiate between pili and fimbriae. How do their structures differ? How do their functions
differ?
5. Compare the cell envelopes of Gram-positive and Gram-negative bacteria. What function does
peptidoglycan serve? To which part of the cell envelope does it belong? Give a simple description of its
structure. What happens to a cell that has its peptidoglycan disrupted or removed? What functions
does the LPS layer serve?
6. What is the Gram stain? What is there in the structure of bacteria that causes some to stain purple
and others to stain red? How does the precise structure of the cell walls differ in Gram-positive and
Gram-negative bacteria? What other properties besides staining are different in Gram-positive and
Gram-negative bacteria? What is the periplasmic space, and how does it function? What characteristics
does the outer membrane confer on Gram-negative bacteria?
7. List five functions that the cell membrane performs in bacteria.
8. Compare the composition of the chromatin body and plasmids. What are the functions of each?
9. What is unique about the structure of bacterial ribosomes? How do they function? Where are they
located?
10. Compare and contrast the structure and function of inclusions and granules. What are
metachromatic granules, and what do they contain?
11. Describe the vegetative stage of a bacterial cell. Describe the structure of an endospore, and
explain its function. Describe the endospore-forming cycle. Explain why an endospore is not considered
a reproductive body. Why are endospores so difficult to destroy?
12. Draw the three bacterial shapes. How are spirochetes and spirilla different? What is a vibrio? A
coccobacillus? What is pleomorphism? What is the difference between the use of the term bacillus and
the name Bacillus? Staphylococcus and staphylococcus?
13. Rank the size ranges in bacteria according to shape. Rank the bacteria in relationship to viruses and
eukaryotic cell size.
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Dr. Raj Ramakrishnan, Ph.D.
14. What characteristics are used to classify bacteria? What are the most useful characteristics for
categorizing bacteria into families? In what ways is ribosomal RNA an important method for
differentiating bacteria and groups of organisms?
15. How is the species level in bacteria defined? Name at least three ways bacteria are grouped below
the species level. In what ways are they important?
16. Describe at least 2 circumstances that give rise to L forms. How do L forms survive? In what ways
are they important? Name several ways in which bacteria are medically and ecologically important.
17. Explain the characteristics of Archaea that indicate it is a unique domain of living things that is
neither a bacterium nor a eukaryote. What leads microbiologists to believe the Archaea are more
closely related to Eukarya than to Bacteria? What is meant by the term extremophile? Describe some
archaeal adaptations to extreme habitats.
Chapter 5
1. Construct a chart indicating the major similarities and differences between prokaryotic and
eukaryotic cells.
2. Which kingdoms of the five-kingdom system contain eukaryotic microorganisms? How do
unicellular, colonial, and multicellular organisms differ from each other? Give examples of each type.
3. Describe the anatomy and functions of each of the major eukaryotic organelles. How are flagella and
cilia similar? How are they different?
4. Compare and contrast the smooth ER, the rough ER, and the Golgi apparatus in structure and
function. Trace the synthesis of cell products, their processing, and their packaging through the
organelle network.
5. Describe the detailed structure of the nucleus. Why can one usually not see the chromosomes?
When are the chromosomes visible? What causes them to be visible?
6. Define mitosis and explain its function. What happens to the chromosome number during this
process? How does a diploid organism remain diploid and a haploid organism remain haploid?
7. Define meiosis and explain its function. When does it occur in diploid organisms? In haploid
organisms? How does it differ from mitosis?
8. Describe some of the ways that organisms use lysosomes.
9. For what reasons would a cell need a "skeleton"?
10. Differentiate between the yeast and hypha types of fungal cell. What is a mold? What does it mean
if a fungus is dimorphic?
11. How does a fungus feed? Where would one expect to find fungi?
12. Describe the functional types of hyphae. Describe the two main types of asexual fungal spores and
how they are formed. What are some types of conidia? What is the reproductive potential of molds in
terms of spore production? How do mold spores differ from prokaryotic spores?
13. Explain the importance of sexual spores to fungi. Describe the three main types, and explain how
each is formed by means of a simple diagram.
14. How are fungi classified? Give an example of a member of each fungus division and describe its
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Dr. Raj Ramakrishnan, Ph.D.
structure and importance.
15. What is a mycosis? What kind of mycosis is athlete’s foot? What kind is coccidioidomycosis?
16. What is a working definition of a "protist"?
17. Describe the principal characteristics of algae that separate them from protozoa. How are algae
important?
18. Explain the general characteristics of the protozoan life cycle. Describe the protozoan adaptations
for feeding. Describe protozoan reproductive processes.
19. Briefly outline the characteristics of the four protozoan groups. What is an important pathogen in
each group?
20. Which protozoan group is the most complex in structure and behavior? In life cycle? What
characteristics set the sporozoa apart from the other protozoan groups?
21. Construct a chart that compares the four groups of eucaryotic microorganisms (fungi, algae,
protozoa, helminths) in cellular structure. Indicate whether the group has a cell wall, chloroplasts,
motility, or some other distinguishing feature. Include also the manner of nutrition and body plan
(unicellular, colonial, filamentous, or multicellular).
Chapter 6
1. Describe 10 unique characteristics of viruses (can include structure, behavior, multiplication). After
consulting table 6.2, what additional statements can you make about viruses, especially as compared
with cells?
2. What does it mean to be an obligate intracellular parasite? What is another way to describe the sort
of parasitism exhibited by viruses?
3. What does it mean to say that viruses are ultramicroscopic? That they are filterable?
4. Describe the general structure of viruses. What is the capsid, and what is its function? How are the
two types of capsids constructed? What is a nucleocapsid? Give examples of viruses with the two
capsid types. What is an enveloped virus, and how does the envelope arise? Give an example of a
common enveloped human virus. What are spikes, how are they formed, and what is their function?
5. What are bacteriophages, and what is their structure? What is a tobacco mosaic virus? How are the
poxviruses different from other animal viruses?
6. Since viruses lack metabolic enzymes, how can they synthesize necessary components? What are
some enzymes with which the virus is equipped?
7. How are viruses classified? Looking at table 6.3, how many different viral diseases can you count?
8. Compare and contrast the main phases in the lytic multiplication cycle in bacteriophages and animal
viruses. When is a virus a virion? What is necessary for adsorption? Why is penetration so different in
the two groups? In simple terms, what does the virus nucleic acid do once it gets into the cell? What is
involved in assembly?
9. What is a prophage or temperate phage? What is lysogeny?
10. What dictates the host range of animal viruses? What are two ways that animal viruses penetrate
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Dr. Raj Ramakrishnan, Ph.D.
the host cell? What is uncoating?
11. Describe the two ways that animal viruses leave their host cell.
12. Describe the different cytopathic effects of viruses. How might it be used to diagnose viral
infection?
13. What does it mean for a virus to be persistent or latent, and how are these events important?
14. Briefly describe the action of an oncogenic virus.
15. Describe the three main techniques for cultivating viruses. What is the advantage of using cell
culture? The disadvantages? What is a disadvantage of using live intact animals or embryos? What is a
cell line? A monolayer? How are plaques formed?
16. What is the principal effect of the agent of Creutzfeldt-Jakob disease? How is the agent different
from viruses? What is a viroid? Why are virus diseases more difficult to treat than bacterial diseases?
17. Circle the viral infections from this list: cholera, rabies, plague, cold sores, whooping cough,
tetanus, genital warts, gonorrhea, mumps, Rocky Mountain spotted fever, syphilis, rubella, rat bite
fever.