Download FIRST HOUR EXAM REGISTRATION NO.: ……… March 25, 2014

GENERAL MICROBIOLOGY
NAME: …………………
FIRST HOUR EXAM
REGISTRATION NO.: ………
March 25, 2014
ENCIRCLE THE CORRECT ANSWER IN THE FOLLOWING
QUESTIONS:
1. Which of the following is considered microorganism?
A. Bacteria B. fungi
C. protozoa
D. all of the above
2. Which of the following provided evidence that a
microorganism could be responsible for a particular disease
A. Koch
B. Leewenhoek C. Pasteur D. none of them
3. The discipline that studies the relationship between
microorganisms and their habitats
A. Agricultural microbiology
B. immunology
C, microbial ecology
D. microbial physiology
4. During the reproductive process, some cells remain
attached to each other to form:
A. Chains
B. terards
C .cubic configuration
D. all of the above
5. Which of the following is (are) function(s) of plasma membrane?
A. it is the location of several metabolic processes
B. separates the cell from its environment
C. serves as a selective permeable membrane
D. all of the above
6. which of the following structures plays a role in cell wall
formation during cell division?
A. mesosomes
B. vesicles
C. pili
D. inclusion bodies
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7. Which of the following is wrong about ribosomes in prokaryotes?
A. consist of proteins and RNA
B. are similar in size to eukaryotic ribosomes
C. are the site for protein synthesis
D. are constructed of 50S and 30S subunits
8. Which Of the following is wrong about plasmids?
A. replicate independently of the chromosome
B. are required for host growth and replication
C. carry genes for drug resistance
D. are extra chromosomal DNA
9. why do Gram positive retain the primary stain while Gram
negative do not?
A. the stain binds to the thick peptidoglycan layer
B alcohol removes the lipids from the outer membrane and thus
the trapped stain
C, alcohol shrinks the pores in the thick peptidoglycan layer,
trapping the stain in the cell
D. answers (B) and (C) are correct
10. which of the following is growth factor
A. vitamins
B. source of carbon
C. trace elements
D. answers A and C
11. Which of the following is a good method for obtaining isolated
pure cultures?
A. spread plates
B. pour plates
C. streak plates
D. all of the above
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12. Which of the following might cause cells to enter the stationary
phase?
A. depletion of essential nutrients
B. lack of available oxygen
C. accumulation of waste products
D. all of the above
13. Which of the following is used as a n electron carrier?
A. Enzyme
B. NADP+
C. ATP
D. all of the above
14. The energy needed for a reaction to occur is called:
A. free energy
B activation energy
C. entropy
D. cofactor
15. Which of the following is associated with group translocation
system ?
A. is active transport
B. requires energy
C. solute molecules move across a membrane without modification
D. all of the above
16. Direct cell counts
A. is the most obvious way to determine microbial numbers
B. is relatively quick
C. gives information about the morphology of the cells
D. All of the above
17. A chemostat
18. Which of the following statements is wrong?
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A. population death usually occurs exponentially
B. smaller populations take longer to kill than larger populations
C. usually higher concentrations or intensities kill more rapidly
D. the longer the exposure to antimicrobial agents the more
organisms are killed
19. Heating liquids at 72°C for 15 seconds followed by rapid
cooling is
A. flash pasteurization
B. ultra high temperature
C. autoclaving
D. lyophilization
20. Which of the following is wrong about ionizing radiation?
A. limited to surface sterilization
B. destroys bacterial endospores
C. used for sterilization and pasteurization of medical products
D. penetrates deep into objects
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MATCHING: PLACE THE LETTER OF EACH TERM IN THE
SPACE INFRONT OF THE STATEMENTS
D.1 Elements required by MO in relatively
large amounts
A. active transport
G.2 MO that obtain electrons from the
oxidation of inorganic compounds
I.3 Transport of 2 substances in the same
direction
C.4 Diffusion process aided by a carrier
M.5 Culture medium that distinguishes
between different groups of bacteria
B. antiport
C. facilitated
diffusion
D. macronutrients
E. trace elements
G. lithotroph
H. organotroph
I.
symport
K. differential medium
M. selective medium
TRUE AND FALSE: WRITE THE LETTER T INFRONT OF THE
CORRECT STATEMENT, AND F INFRONT OF THE WRONG
STATEMENT. THEN CORRECT THE UNDERLINED IN FALSE
STATEMENTS
……………….1. Gas vacuoles are membranous structures that
regulate buoyancy in cyanobacteria
T
……………….2. Teichoic acids are connected to the cell wall in
Gram negative bacteria
F, +ve
………………..3. Capsules protect the cell from dessication
T
………………..4. flagella which are distributed evenly around the
cell are called amphitrichous
F, peri………………..5. In E. coli, the peptidoglycan strands of the cell
wall are directly linked.
T
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………………..6. the most common types of Gram positive cell
walls is an S-layer composed of glycoprotein or protein F,
archeae
…………………7. Dry heat sterilization is generally faster than
moist heat sterilization
F, slower
…………………8. A sterile object is completely free of viable MO
T
FILL IN THE SPACES AS APPROPRIATE
1. The science of classifying organisms is called
…………………taxonomy and the groups making up
the classification hierarchy are called taxa
2. The first, largest, and most inclusive group under
which organisms are classified is called a…………….
domain.
3. Woese proposed a phylogenetic tree based on……………….
Sequence analysis rRNA
4. ……………………..are MO that require low water activity for
their growth
halophiles
5. …………………….. are MO that have optima at 80-90oC
thermophiles
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IDENTIFY THE FOLLOWING DIAGRAMS AND THE
STRUCTURES POINTED AT
Plasma membrane
endospore
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