Biofilms & Culture Media
Clue: These microbial structures are described as 'complex and dynamic ecosystems.'
What are biofilms?
Clue: The primary method of asexual reproduction in bacteria.
What is binary fission?
Clue: The phase where bacteria are metabolically active but not dividing.
What is the lag phase?
Clue: These oxygen-loving microbes include Mycobacterium tuberculosis.
What are obligate aerobes?
Clue: This method uses a calibrated slide and microscope to count cells.
What is direct microscopic cell count?
Clue: Biofilms often form on these medical items, leading to HAIs.
What are catheters (or medical devices)?
Clue: This structure builds the septum between daughter cells during binary fission.
What is the divisome?
Clue: The phase where cells are most susceptible to antibiotics.
What is the log (exponential) phase?
These organisms tolerate but do not use oxygen.
What are aerotolerant anaerobes?
Clue: This method counts only viable cells that form colonies.
What is a plate count (viable plate count)?
Clue: This general-purpose medium supports a wide range of microbes.
What is tryptic soy broth (TSB)?
Clue: The phase where the cell replicates DNA in preparation for division.
What is the growth phase before cytokinesis?
Clue: This phase is marked by an equal rate of cell growth and death.
What is the stationary phase?
Clue: These microbes grow best in high CO₂, low O₂ environments.
What are capnophiles?
Clue: This device measures electrical resistance to count cells.
What is a Coulter counter?
Clue: These media allow visual differentiation of bacterial colonies.
What are differential media?
In cell division, this part divides during cytokinesis.
What is the cytoplasm?
Clue: Secondary metabolites like antibiotics are often produced in this phase.
What is the stationary phase?
Clue: Organisms like Vibrio cholerae thrive in this pH range.
What is alkaline (8.0–10.5)?
Clue: This indirect method measures turbidity using this instrument.
What is a spectrophotometer?
Clue: This medium helps grow fastidious organisms by adding nutrients.
What is enriched media?
Clue: An alternative to binary fission where a new cell forms from a bud on the parent.
What is budding?
Clue: The phase characterized by a decline in cell numbers.
What is the death (decline) phase?
Clue: These salt-loving organisms live in high-saline environments.
What are halophiles?
This method estimates cell biomass by drying and weighing it.
What is dry weight measurement?