AL-Majmaah University
College of Apllied Medical science
Medical Laboratory Science Department
Date: 14-1-1435, Time: One hour
Student name: …………………………………………………………………
ID: ……………………………
General Microbiology – 1st mid-term exam (MDL-234)
Answer on the following question
I- Choose the correct answer (put circle)?
1. The oldest eukaryotic organisms are considered to be The oldest eukaryotic
organisms are considered to be
a. diplomonads like Giardia
b. archaea
c. fungi
d. animals
2. The bacteria cell walls have a large amounts of peptidoglycans that react with
Gram’s stain are
a. Gram-negative bacteria
c. Acidic bacteria
d. Basic bacteria
b. Gram-positive bacteria
3. Mycoplasmas are different from the other prokaryotes by Composed of three
subunits
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
4. 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
5. All membranes of free-living organisms have phospholipid bilayers, but exception
is
a.
bacteria
b.
fungi
c.
archaea
d.
protozo
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6. Gram positive (Gram +ve) bacteria are non-pathogenic stained … with Gram Staining
a. No Staining
c. Red
b. Violet
d. Green
7.
Which of the following structure is present in prokaryotic cells?
a.
Mitochondria
b.
Chloroplasts
c.
Golgi structure
d.
Mesosome
8.
Flagella move the cell by
a.
many flagella beating in a synchronous, whip-like motion
b.
an individual flagellum beating in a whip-like motion
c.
spinning like a propeller
d.
attaching to nearby particles and contracting
9.
Which of the following may contain fimbriae?
a.
Gram-positive bacteria
b.
Gram-negative bacteria
c.
Both (a) and (b)
d.
None of these
10. Which
of the following is true about cell wall of gram-positive bacteria?
a.
It consists of multiple layers
b.
It is thicker than that associated with gram-negative bacteria
c.
It contains teichoic acids
d.
All of these
11. The
cocci which forms a bunch and irregular pattern are
A.
Staphylococci
B.
diplococci
C.
Tetracocci
D.
Streptococci
12. Periplasm
is
a.
the area between the inner and outer membranes of gram-negative bacteria
b.
the area between the inner and outer membranes of Gram-positive bacteria
c.
the interior portion of mitochondria
d.
the area outside the cell membrane that is influenced by the polymers
13. The
bacteria deficient in cell wall is
a.
Treponema
b.
Mycoplasma
c.
Staphylococcus
d.
Klebsiella
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14. Which
of the following bacterial genera (that produces endospore) have medical
importance?
a.
Clostridium
b.
Bacillus
c.
Both (a) and (b)
d.
None of these
15. Teichoic
acids are typically found in
a.
cell walls of gram positive bacteria
b.
outer membranes of gram positive bacteria
c.
cell walls of gram negative bacteria
d.
outer membranes of gram negative bacteria
16. Chemically
the bacterial capsule may be
a.
Polypeptide
b.
polysaccharide
c.
either (a) or (b)
d.
none of these
17. Which
of the following is not the characteristic of a growth curve?
a.
Shows development of microbial population under relatively stable environmental conditions
b.
Plotted with logarithmic numbers
c.
Graphs numbers of microbes versus time
d.
Each growth curve consists of four distinct phases
18. Which
of the following organisms typically get their carbon for biosynthesis from
carbon dioxide?
a.
Glucose-fermenting bacteria (fermentation)
b.
Anaerobic, glucose-respiring bacteria (anaerobic respiration)
c.
Aerobic, glucose-respiring bacteria (aerobic respiration)
d.
Ammonia-oxidizing bacteria (chemolithotrophic bacteria)
19. An
organism has an optimal growth rate when the hydrogen ion concentration is
very high. This organism is
a.
osmotolerant
b.
acidophile
c.
neutrophile
d.
aerotolerant anaerobe
20. A
culture broth tube was very turbid at the surface but clear throughout the rest of
the tube indicating that the
a.
organism are aerobes
b.
organism should be grown in an anaerobic chamber
c.
organism cannot produce superoxide dismutase and/or catalase
d.
organism cannot tolerate oxygen
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21. 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
II- Put True or False correct the wrong one?
1. (----f----) Nucleoid is bounded by nuclear membrane
2. (----f----) Chromosomes does not contain genes
3. (----T----) 80S ribosomes are distributed in cytoplasm
4.
(----T----) Cell wall contains peptidoglycan as one of the major component
5.
(----f----) The term facultative anaerobe refers to an organism that is killed by oxygen
6.
(----f----) All bacteria are prokaryotes
7.
(----f----) Prokaryotic cells divide by mitosis
8.
(----T----) Prokaryotes exist in extreme environments (hot and salty) called Archaea
9.
(----F----) Gram-positive species are pathogenic more threatening than gramnegative species.
III. Write a few sentences describing each of the following that we met in our first lecture
1. What is the microbiology
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2. Beneficial of bacteria:
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3. Dangerous of bacteria
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IV- Write the correct words or expressions:
1. The cell walls of many gram positive bacteria can be easily destroyed by the enzyme known
as………………………………….
2. The common word for bacteria which are spherical in shape is…………………………………………………
3. The location where the bacterial chromosome concentrates is called………………………………………..
4. Generation time of Escherichia coli is………………………………………..
5. The organism which obtain their energy from chemicals are designated as……………………………………..
6. The organism which grows best above 45°C are called………………………………………………………
7. The cell reproduction in bacteria may occur by………………………………………………………..
8. The microorganisms that grow best in a low-oxygen environment is called a
(n)………………………………………………………….
9. Steam exposure of a material at 100°C for 20 minutes for three consecutive days is known
as………………………………………………………………..
10.
The ……………………contains most of the genes in an eukaryotic cell.
11.
Most bacterial cell walls contain a polymer of modified sugars cross-linked by short
polypeptides called………………………………
Good luck
Dr. El-Safey
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