#1
Which method is commonly used to sterilize culture media in microbiology?
Autoclaving
Filtration
Chemical disinfection
UV irradiation
#2
Which of the following is NOT a characteristic of a pure culture?
Consists of a single species of microorganism
Uniform appearance throughout the culture
May contain multiple species of microorganisms
Obtained from a single colony
#3
Which of the following is NOT a method for preserving bacterial cultures?
Freezing at -80°C
Lyophilization (freeze-drying)
Subculturing at regular intervals
Storing at room temperature
#4
Which of the following agar media is commonly used for the isolation of fastidious bacteria?
Blood agar
MacConkey agar
Mannitol salt agar
Sabouraud agar
#5
Which of the following is a common method for bacterial identification based on DNA sequences?
Gram staining
Biochemical tests
Polymerase chain reaction (PCR)
Electron microscopy
#6
What is the purpose of streaking a bacterial culture onto agar plates?
To isolate individual bacterial colonies
To increase the number of bacteria in the culture
To identify bacterial species
To remove contaminants from the culture
#7
Which of the following is NOT a method for counting bacterial colonies on an agar plate?
Serial dilution
Direct microscopic count
Spread plate method
Pour plate method
#8
What is the purpose of a selective medium in bacterial culture?
To promote the growth of a particular group of bacteria
To inhibit the growth of unwanted bacteria
To determine the total bacterial count
To visualize bacterial colonies
#9
What is the purpose of a bacterial growth curve?
To determine the optimal temperature for bacterial growth
To visualize the growth stages of bacteria over time
To calculate the doubling time of bacteria
To measure the rate of bacterial metabolism
#10
Which of the following is NOT a factor affecting bacterial growth?
Temperature
pH
Humidity
Atmospheric pressure
#11
Which staining technique is commonly used to differentiate between Gram-positive and Gram-negative bacteria?
Acid-fast staining
Capsule staining
Endospore staining
Gram staining
#12
Which of the following is a common method for determining bacterial susceptibility to antibiotics?
Minimum inhibitory concentration (MIC) assay
Serial dilution method
Direct microscopic count
Gram staining
#13
Which of the following is NOT a method for determining bacterial motility?
Hanging drop method
Stab inoculation method
Flagella staining
Swarming assay
#14
Which of the following is a common method for bacterial transformation?
Conjugation
Transduction
Electroporation
Phagocytosis
#15
Which of the following is NOT a component of bacterial cell walls?
Peptidoglycan
Lipopolysaccharide (LPS)
Chitin
Teichoic acid