WorksheetsBMOL6401 - L6 - Microbial Population Growth and Control
Total questions: 75
Worksheet time: 38mins
Name
Class
Date
1.
Define binary fission
a)
The division of a single cell into four
b)
Cell division following enlargement of the cell
c)
The fusion of two cells
d)
A process where cells exchange DNA
2.
Define generation time
a)
Time required for microbes to double in number
b)
The time it takes for a single cell to divide
c)
The duration of the lag phase
d)
Time it takes for two cells to merge
3.
The process by which two prokaryotic cells arise from one is known as…
a)
Mitosis
b)
Binary fission
c)
Meiosis
d)
Cytokinesis
4.
Define mitosis
a)
The process by which two cells arise from one
b)
Cell division that results in two genetically identical cells
c)
The division of two cells into four
d)
A process unique to prokaryotic cells
5.
Define meiosis
a)
Cell division that results in four haploid cells
b)
The process that produces two genetically identical cells
c)
The process of DNA replication
d)
A method of binary fission
6.
What is the role of the septum in binary fission?
a)
It forms a ring around the chromosomes
b)
It connects the FtsZ ring to the membrane
c)
It facilitates separation of daughter cells
d)
It splits the cell into two
7.
Put these processes of bacterial replication in the correct order
a)
A, B, D, C
b)
C, B, D, A
c)
A, C, B, D
d)
C, D, A, B
8.
What are the key proteins in cell division known as?
a)
Flagella proteins
b)
Min proteins
c)
Fts proteins
d)
Tubulin proteins
9.
What is the role of FtsZ in cell division?
a)
Forms a contractile ring around the center of the cell
b)
Anchors Fts proteins to the cell membrane
c)
Aids in chromosome replication
d)
None of the above
10.
What is the role of ZipA in cell division?
a)
Separates daughter cells
b)
Anchors FtsZ ring to the membrane
c)
Connects chromosome ends
d)
Stabilizes chromosome segregation
11.
What is the role of FtsA in cell division?
a)
Assists in chromosome replication
b)
Connects FtsZ ring to membrane and recruits divisome proteins
c)
Stabilizes cell shape
d)
Facilitates cell membrane synthesis
12.
What is the role of FtsK in cell division?
a)
Mediates chromosome separation
b)
Forms the FtsZ ring
c)
Anchors the FtsZ ring to membrane
d)
Initiates cytokinesis
13.
Location of FtsZ ring is facilitated by…
a)
Min proteins
b)
FtsA proteins
c)
Flagella proteins
d)
MreB proteins
14.
Which protein separates DNA?
a)
FtsK
b)
ZipA
c)
MreB
d)
FtsZ
15.
What guides the FtsZ to the midpoint of the cell?
a)
MreB proteins
b)
MinC, D, and E proteins
c)
Flagella proteins
d)
Divisome proteins
16.
What might happen if the septum didn’t form during binary fission?
a)
Nothing, the septum is not required for binary fission
b)
The chromosome could not replicate
c)
The parent cell would have two copies of the chromosome
d)
Daughter cells would not be genetically identical
17.
In microbiology, growth is defined as an increase in…
a)
Cell size
b)
Population size
c)
Cell number
d)
Cell wall thickness
18.
Generation time can be calculated by…
a)
g = t/n where t is time and n is number of generations
b)
g = n/t where n is the number of cells
c)
g = t + n where t is time
d)
None of the above
19.
The number of generations is the same as number of cells (true or false?)
a)
True
b)
False
20.
Define binary fission (cell division following enlargement of cell to twice its minimum size)
a)
Cell division in bacteria
b)
Cell elongation and separation
c)
Enlargement of cells
d)
Increase in cell size and splitting
e)
All of the above
21.
Define generation time (time required for microbes to double in number)
a)
Time taken for one cell to divide
b)
Time taken for microbes to double in number
c)
Time required for genetic replication
d)
Time required for cell separation
e)
-
22.
The process by which two prokaryotic cells arise from one is known as...
a)
Mitosis
b)
Meiosis
c)
Binary fission
d)
Cell elongation
e)
-
23.
Define mitosis
a)
Division of bacterial cells
b)
Division of eukaryotic cells
c)
Binary fission in eukaryotes
d)
Replication of prokaryotic cells
e)
-
24.
Define meiosis
a)
Cell elongation
b)
Sexual reproduction in bacteria
c)
Cell division for genetic diversity
d)
Binary fission
e)
-
25.
What is the role of the septum in binary fission?
a)
Cell elongation
b)
Chromosome replication
c)
Division of cytoplasm
d)
Separation of daughter cells
e)
All of the above
26.
Put these processes of bacterial replication in the correct order: a - Cell elongation, b - Septum formation, c - Chromosome replication, d - Separation of daughter cells
a)
A, C, B, D
b)
C, B, A, D
c)
B, A, C, D
d)
A, B, C, D
e)
A, D, B, C
27.
What are the key proteins in cell division known as?
a)
Z proteins
b)
Fts proteins
c)
G proteins
d)
Tubulin proteins
e)
None of the above
28.
What is the role of FtsZ in cell division?
a)
Anchors cytoplasm
b)
Forms rings around center of the cell
c)
Mediates DNA replication
d)
Helps connect proteins to membrane
e)
-
29.
What is the role of ZipA in cell division?
a)
Forms FtsZ rings
b)
Anchors FtsZ ring to cytoplasmic membrane
c)
Separates chromosomes
d)
Aids in DNA replication
e)
None of the above
30.
What is the role of FtsA in cell division?
a)
Helps connect FtsZ ring to membrane
b)
Forms the septum
c)
Aids in cell elongation
d)
Facilitates chromosome replication
e)
None of the above
31.
What is the role of FtsK in cell division?
a)
Forms FtsZ ring
b)
Helps in septum formation
c)
Facilitates chromosome separation to daughter cells
d)
Aids in anchoring ZipA
e)
-
32.
Location of FtsZ ring is facilitated by...
a)
Min proteins
b)
FtsK
c)
ZipA
d)
G proteins
e)
-
33.
Which protein separates DNA?
a)
FtsZ
b)
MinD
c)
FtsK
d)
FtsA
e)
-
34.
What guides the FtsZ to the midpoint of the cell?
a)
MinA, B, and C
b)
MinE, C, and D
c)
MinC, D, and E
d)
MinA, D, and E
e)
-
35.
What might happen if the septum didn’t form during binary fission?
a)
The parent cell would have two copies of the chromosome
b)
The chromosome would not replicate
c)
The daughter cells would not be genetically identical
d)
Nothing would happen
e)
-
36.
In microbiology, growth is defined as an increase in...
a)
Cell size
b)
Cell organelles
c)
Population
d)
Cytoplasmic volume
e)
-
37.
Generation time can be calculated by...
a)
g = t/n; where t is time and n is the number of generations
b)
g = n/t; where n is number of cells and t is time
c)
g = n - t; where t is the number of cells
d)
g = time taken for replication/n number of cells
e)
-
38.
The number of generations is the same as number of cells
a)
True
b)
False
c)
-
d)
-
e)
-
39.
The time interval required for the formation of two cells from one is called the...
a)
Replication time
b)
Cell cycle
c)
Generation time
d)
Lag phase
e)
-
40.
Most common way of performing viable cell count is by using…
a)
Microscopic count
b)
Plate counts
c)
Flow cytometry
d)
Spectrophotometry
e)
-
41.
The two main ways of performing plate counts are…
a)
Spread plate and streak plate methods
b)
Pour plate and streak plate methods
c)
Spread plate and pour plate methods
d)
Microscopic count and optical density
e)
-
42.
Compare spread plate and pour plate methods of enumerating microorganisms
a)
Spread plate allows even growth on surface, while pour plate includes colonies throughout agar
b)
Spread plate is quicker than pour plate
c)
Pour plate ensures aerobic conditions only
d)
Spread plate requires less sample
e)
-
43.
How to calculate cell per milliliter of original sample if you have found 159 colonies on a plate that is a 10^-3 serial dilution of the original sample
a)
1.59 x 10^6 cells/mL
b)
1.59 x 10^4 cells/mL
c)
1.59 x 10^3 cells/mL
d)
159 x 10^3 cells/mL
e)
-
44.
What is flow cytometry and how to use it to estimate the cell count of a sample of microorganisms?
a)
Measures optical density
b)
Uses lasers to count and sort cells based on size and shape
c)
Uses a grid to calculate the number of live cells
d)
Detects chemical changes in cell structure
e)
-
45.
The number of organisms in a broth culture was determined using the standard plate count (SPC) and spectrophotometry (SPEC). Which result would you most likely expect from each method?
a)
SPC = SPEC
b)
SPC > SPEC
c)
SPC < SPEC
d)
SPC > 100 cells/ml and SPEC = 10 cells/ml
e)
-
46.
What is the great plate anomaly?
a)
Microscopic counts of natural samples reveal more organisms than plate counts
b)
Plate counts of natural samples reveal more organisms than microscopic counts
c)
Dead cells can replicate
d)
All bacteria grow equally in both conditions
e)
-
47.
Viable cell counting: are cells either alive or dead?
a)
Yes
b)
No, they can have intermediate states like being dormant
c)
Only dead cells are visible
d)
Plate counts count only dead cells
e)
-
48.
Are plate counts reliable when used to assess total cell numbers of natural samples?
a)
Yes
b)
No, different organisms have different requirements for growth
c)
Sometimes
d)
Only in specific environments
e)
-
49.
A student wants to know how many living cells are in his pure culture, which method should be used?
a)
Microscopic counts
b)
Plate counts
c)
Turbidity measurements
d)
Optical density
e)
-
50.
How can we control microbial growth?
a)
Physical agents
b)
Chemical agents
c)
Mechanical removal
d)
Biological agents
e)
All of the above
51.
Define disinfection
a)
Complete removal of all microorganisms
b)
Destruction or removal of vegetative pathogens but not endospores
c)
Chemicals applied to body surfaces to destroy pathogens
d)
Chemicals used internally to kill microorganisms
e)
-
52.
Define sterilization
a)
Complete removal of all viable microorganisms
b)
Removal of vegetative pathogens
c)
Removal of only endospores
d)
Inhibition of microbial growth
e)
-
53.
Define antisepsis
a)
Removal of microorganisms from body surfaces
b)
Complete removal of all microorganisms from surfaces
c)
Use of heat to remove pathogens
d)
Use of UV light to inhibit growth
e)
-
54.
Define chemotherapy
a)
Use of heat to remove pathogens
b)
Use of chemical agents internally to kill microorganisms
c)
Inhibition of microbial growth
d)
Use of UV light to sterilize liquids
e)
-
55.
Most common way of controlling microbial growth?
a)
Heat sterilization
b)
UV radiation
c)
Membrane filtration
d)
Chemical agents
e)
-
56.
Amount of time required to reduce viability tenfold is called the…
a)
Decade reduction time
b)
Decimal reduction time
c)
Tenfold reduction time
d)
Half-life reduction time
e)
-
57.
Some bacteria produce resistant cells called _________ that can survive heat that would rapidly kill off vegetative cells.
a)
Endospores
b)
Fimbriae
c)
Capsules
d)
Pili
e)
-
58.
To heat sterilize samples, we use an _______ that uses ____________ to kill microorganisms.
a)
UV light, pressure
b)
Autoclave, steam under pressure
c)
Filter, high temperature
d)
Incubator, heat
e)
-
59.
___________ is the process of applying short heat duration to reduce microbial loads in heat-sensitive liquids, such as milk.
a)
Sterilization
b)
Pasteurization
c)
Disinfection
d)
Antisepsis
e)
-
60.
A unpressurized autoclave would not be able to sterilize a growth medium with contaminating bacteria but would still pasteurize it.
a)
True
b)
False
61.
Pasteurization is the complete removal of bacteria and microorganisms.
a)
True
b)
False
62.
What is a downside of using UV radiation to sterilize?
a)
Cannot penetrate solid or opaque surfaces
b)
Only works on liquids
c)
Causes mutations in DNA
d)
Kills endospores
63.
Depth filters (HEPA) and membrane filters act as a…
a)
Biological control
b)
Mechanical removal
c)
Physical control
d)
Chemical control
64.
A microbiologist wants to study virus particles from a urine sample, but not any bacteria that is present. How should he eliminate the bacteria without eliminating the virus?
a)
Expose to UV light
b)
Filter the sample with a 0.2µm pore filter
c)
Expose sample to ionizing radiation
d)
Autoclave the sample
65.
How does penicillin work?
a)
Inhibits ribosome function
b)
Binds to proteins involved in cell wall synthesis, preventing cross-linking
c)
Inhibits DNA replication
d)
Destroys RNA
66.
How does tetracycline work?
a)
Inhibits ribosomes of bacteria, preventing protein synthesis
b)
Prevents cell wall synthesis
c)
Inhibits DNA replication
d)
Disrupts cell membrane
67.
How does ciprofloxacin work?
a)
Inhibits ribosomes
b)
Inhibits cell wall synthesis
c)
Inhibits DNA replication
d)
Destroys lipids in the cell membrane
68.
What does the suffix '-static' mean?
a)
Inhibits
b)
Kills
c)
Kills and lyses
d)
Represses
69.
What does the suffix '-cidal' mean?
a)
Inhibits
b)
Kills
c)
Kills and lyses
d)
Represses
70.
What does the suffix '-lytic' mean?
a)
Inhibits
b)
Kills
c)
Kills and lyses
d)
Represses
71.
Is penicillin bacteriocidal or bacteriostatic?
a)
Bacteriocidal
b)
Bacteriostatic
c)
Both
d)
Neither
72.
Is tetracycline bacteriocidal or bacteriostatic?
a)
Bacteriocidal
b)
Bacteriostatic
c)
Both
d)
Neither
73.
What does MIC stand for?
a)
Maximum inhibitory concentration
b)
Minimum inhibitory concentration
c)
Minimum inactive concentration
d)
Maximum inactive concentration
74.
What is biological control of microorganisms?
a)
Use of chemical agents
b)
Use of heat
c)
Use of natural control mechanisms, such as predation or viral-mediated lysis
d)
Use of UV radiation
75.
Which term is most relevant when describing the efficacy of an antimicrobial for use in a clinical setting?
a)
Maximum inhibitory concentration
b)
Minimum inhibitory concentration
c)
Minimum active concentration
d)
Maximum bacteriocidal concentration
100 %
