MCB 229 Spring 2000 Study Guide 1 Prof.
Terry
Covers Lectures for Jan. 27 and Feb. 1
This study guide is intended for you to use while you are
doing the assigned text reading. Quiz questions will be made with reference to
topics in this study guide. This guide covers assigned reading for the first 2
lectures. Subsequent study guides will cover the assigned reading for each
lecture.
Note: Quiz #1, based on questions from this study guide, must
be completed by midnight before the class on Tues. Feb. 1. You will need to
create your "myWebCT" account and visit the MCB 229 WebCT page in order to
access this quiz. Quizzes count towards your course grade: don't
procrastinate!
Chapter 1
- What organisms are studied by microbiology? Are all organisms in these
groups invisibly small? If not, why are they called "micro-" organisms?
- What
major contributions were made by each of the following individuals?
Antony
van Leeuwenhoek
Louis Pasteur
Robert Koch - Look at Table 1.1, which
lists important historical events. Answer the following questions:
- In what year did Leeuwenhoek discover his
"animalcules"?
- When did Pasteur discover that
fermentation was caused by a microbe?
- When did
Koch discover that anthrax was caused by a particular bacterium (Bacillus
anthracis)?
- When did Pasteur discover the
rabies vaccine?
- When did Ehrlich develop the
first chemotherapeutic agent (for
syphillis)?
- When did Fleming discover
penicillin?
- When did Waksman discover
streptomycin?
- When was the first genome (the
bacterium Haemophilus influenzae) sequenced?
- Joseph Lister is a household word today (listerine). What is he best known
for historically?
- The history of the "spontaneous generation controversy" is
a convoluted one (see text pp. 2-7).
- What did proponents of spontaneous generation
argue?
- What did opponents of spontaneous
generation claim?
- How did Pasteur resolve this
issue? What role did his swan neck flasks play in this process?
- What are Koch's postulates? Why were they important?
- The period from
roughly 1880-1920 is sometimes called the "golden age" of microbiology. Why do
you think this is the case? (Hint: look at Table 1.2) What did this golden age
accomplish?
- Two famous microbiologists whose names are not household words
are Sergei Winogradsky and Martinus Beijerinck. In what way did they make major
contributions to microbiology?
- What is the basic difference between
procaryotic and eucaryotic cells? To which of these groups do each of the
following belong: fungi, viruses, bacteria, animals.
- What are the 5
Kingdoms? Which include microbes?
- What are the 3 Domains (or empires)? Which
include microbes?
Chapter 2
- You should be familiar with the metric system, especially with prefixes for
small sizes. What do each of the following mean: (a) nano- ; (b) milli- ; (c)
micro- ?
- Virus A is measured to be 200 nanometers; bacterium B is measured
to be 0.15 micrometers. Which is larger?
- Resolving power depends on 2
things: what are they? How can you improve r.p. for light microscopy? Note the
equation on p. 19.
- What is the r.p. of a light microscope, expressed in
micrometers?
- For what purposes might you want to use each of the following
microscopes: darkfield, phase-contrast, fluorescence?
- Identify two
techniques for fixing bacteria.
- What is the difference between a simple
stain and a differential stain? Give 2 examples of differential stains.
- What
is the approximate resolving power of a transmission electron microscope (TEM)?
What preparation steps are necessary before an object can be viewed in
TEM?
- How does a scanning electron microscope (SEM) differ from a TEM? You
should be able to recognize whether a photo is taken with light, SEM, or
TEM.
Chapter 3 (pp. 37-51)
- What are the common shapes of bacteria? What do the following terms
mean:
- coccus
- bacillus
- vibrio
- spirillum
- spirochete
-- is this synonymous with the previous
term?
- pleiomorphic
- Examine Figure 3.3. What are the dimensions of the smallest cell shown, in
nm? In micrometers? How big is the biggest virus shown, in comparison to the
smallest cell shown? Considerable controversy surrounds the possible existence
of "nanobacteria" (also called ultramicrobacteria); how large are these
organisms?
- "Procaryotes are smaller than eucaryotes." Is this statement
true? (Hint: see box 3.1)
- Table 3.1 summarizes the functions of common
procaryotic structures. What function(s) are ascribed to each of the
following:
- Periplasmic
space
- Endospore
- Fimbriae
and pili
- Plasma
membrane
- Cell
wall
- Flagella
- Capsules
and slime layers
- Ribosomes
- What do the following terms mean: hydrophilic, hydrophobic, amphipathic?
Which cell structure is made largely from amphipathic molecules?
- Hopanoids
are bacterial molecules found in _____________ ; although unique to bacteria,
they resemble ________________, a molecule found in animal cell membranes.
Compared with other organic molecules, are hopanoids scarce or
abundant?
- Mesosomes are internal membranous structures seen in some
bacterial cells by TEM after certain types of fixation (see p. 43). They have
not been physically isolated, and most microbiologists regard them as artifacts,
although they may correspond to certain functionally specialized regions of the
cell. If so, this function remains unknown. Are there any other internal
membranes in bacteria? Are they found in all or only in certain bacteria?
- What is the cellular location and possible function of each of the
following: poly-beta-hydroxybutyric acid, glycogen, polyphosphate granules
(volutin), gas vacuoles, sulfur granules?
- Where are ribosomes found, and
what do they do? Ribosomes contain 30S and 50S subunits. What is the S value of
a bacterial ribosome (containing both subunits)? What is the S value of a
eucaryotic ribosome?
- What is (are) the function(s) of molecular chaperones?
Under what environmental conditions do chaperone concentrations
increase?
- What is the bacterial nucleoid? How does it differ from a nucleus?
How many individual molecules of DNA does it contain? What is a plasmid?
