UTA MICROBIOLOGY EXAM
UTA MICROBIOLOGY EXAM 3 2025
EXAM QUESTIONS WITH VERIFIED
ANSWERS
4 Basic Steps of binary fission - 1. Growth of cell size
2. Replication of DNA
3. Division of cytoplasm
4. Septum formation & cell division
Z Ring Assembly - FtsZ assembles Z ring to form divisome
Generation Time - time it takes to double the population
Lag Phase - Cells adjust to culture medium; no change in population
What factors determine the duration of the lag phase? - Genetic makeup, media
composition, initial inoculum size
During which phase of the growth curve is it most appropriate for the use of antibiotics? -
Log phase
Following the death phase of the growth curve, ____ cells are considered the surviving
cells & are considered clinically important due to their association with chronic
infections, such as Tuberculosis. - Persisters
Log Phase - Binary fission occurs; cell replication > cell death
UTA MICROBIOLOGY EXAM
,UTA MICROBIOLOGY EXAM
Stationary Phase - Resources become depleted; cell respiration=cell death
Death Phase - Endospores can form; cell replication < cell death
Close System Cultures - Have finite resources
Open System Cultures - -Nutrients and air are replenished
-Dead cells and waste are removed
-Beneficial for industrial microbiology
Microscopic Cell Count - Cells are counted under a microscope using a laser etched slide
In using the direct microscopic cell count method, you will be able to distinguish between
live vs dead cells. - False
Fluorescence Staining - Cells are counted under a microscope or flow cytometer
In fluorescent staining, the end product results in live cells staining ___________? -
Green
In fluorescent staining, the end product results in dead cells staining ___________? - Red
Coulter counting - Detects electrical resistance change due to cell density
Viable Cell Counts - Samples are diluted and grown on solid media
UTA MICROBIOLOGY EXAM
, UTA MICROBIOLOGY EXAM
What type of cells are counted when using the viable plate count method? - Living
Countable Range - 30-300 CFU/ml
Optical Density - -Measured with spectrophotometer
-Light is passed thru culture and measured on other side
Which method of measuring growth is considered an indirect approach? - Optical density
Which method of measuring growth can be used on living or dead cells? - Fluorescent
stain
How is the pour plate technique set up? - The sample is mixed with a warm agar ranging
from 45-50 C, poured onto sterile plated and swirled to mix
How is the spread plate technique set up? - The sample is poured onto a solid medium
and spread using a L spreader
What cell counting method is used for counting colonies from drinking water? -
Membrane filtration
What method of measuring growth is used in food/water testing? - MPN (most probable
number)
Steps of Biofilm Formation - 1. Attachment of planktonic cells
2. Cells become sessile
UTA MICROBIOLOGY EXAM
UTA MICROBIOLOGY EXAM 3 2025
EXAM QUESTIONS WITH VERIFIED
ANSWERS
4 Basic Steps of binary fission - 1. Growth of cell size
2. Replication of DNA
3. Division of cytoplasm
4. Septum formation & cell division
Z Ring Assembly - FtsZ assembles Z ring to form divisome
Generation Time - time it takes to double the population
Lag Phase - Cells adjust to culture medium; no change in population
What factors determine the duration of the lag phase? - Genetic makeup, media
composition, initial inoculum size
During which phase of the growth curve is it most appropriate for the use of antibiotics? -
Log phase
Following the death phase of the growth curve, ____ cells are considered the surviving
cells & are considered clinically important due to their association with chronic
infections, such as Tuberculosis. - Persisters
Log Phase - Binary fission occurs; cell replication > cell death
UTA MICROBIOLOGY EXAM
,UTA MICROBIOLOGY EXAM
Stationary Phase - Resources become depleted; cell respiration=cell death
Death Phase - Endospores can form; cell replication < cell death
Close System Cultures - Have finite resources
Open System Cultures - -Nutrients and air are replenished
-Dead cells and waste are removed
-Beneficial for industrial microbiology
Microscopic Cell Count - Cells are counted under a microscope using a laser etched slide
In using the direct microscopic cell count method, you will be able to distinguish between
live vs dead cells. - False
Fluorescence Staining - Cells are counted under a microscope or flow cytometer
In fluorescent staining, the end product results in live cells staining ___________? -
Green
In fluorescent staining, the end product results in dead cells staining ___________? - Red
Coulter counting - Detects electrical resistance change due to cell density
Viable Cell Counts - Samples are diluted and grown on solid media
UTA MICROBIOLOGY EXAM
, UTA MICROBIOLOGY EXAM
What type of cells are counted when using the viable plate count method? - Living
Countable Range - 30-300 CFU/ml
Optical Density - -Measured with spectrophotometer
-Light is passed thru culture and measured on other side
Which method of measuring growth is considered an indirect approach? - Optical density
Which method of measuring growth can be used on living or dead cells? - Fluorescent
stain
How is the pour plate technique set up? - The sample is mixed with a warm agar ranging
from 45-50 C, poured onto sterile plated and swirled to mix
How is the spread plate technique set up? - The sample is poured onto a solid medium
and spread using a L spreader
What cell counting method is used for counting colonies from drinking water? -
Membrane filtration
What method of measuring growth is used in food/water testing? - MPN (most probable
number)
Steps of Biofilm Formation - 1. Attachment of planktonic cells
2. Cells become sessile
UTA MICROBIOLOGY EXAM
