Exam 2 Prep Flashcards
Define log or exponential growth phase
Cultures are accustomed to environmental conditions
Rapid growth/shortest generation time
Cells tend to be their largest.
Drugs are most effective.
Define lag phase of bacterial growth curve.
Little to no growth
cells need time to detect environment
turn on/off genes necessary to use nutrients available in the environment
Length of legacies waries depending on differences between old and new environments
Define stationary phase
Growth rate equals death rate as nutrients decrease and waste products accumulate.
Approximately 1 billion cells per milliliter.
Sporulation phase begins.
Define death/decline phase
Without nutrients, all cells begin to die. Death rate is exponential.
What is the apparatus called in which a continuous culture is produced?
Chemostat, uniform growth.
Viral one step growth curve cell life cycle basics
Attachment, penetration, synthesis(transcription/translation), release of virus, building of the virus if it is enveloped
Steps of the viral one step growth curve
Decline phase-virus attaches and penetrates the cell
Eclipse phase-synthesis
Rise phase-being released from cell and are budding
Burst size=final-initial
Serial dilutions are used for ________ samples; filtration will be used on __________ samples.
Concentrated,dilute
Define CFU
Colony forming unit
Bacterial pop equation
Number of colonies / dilution
Standard plate count for viruses is called a….
Plaque assay
Plaque assays-area of dead cells that appears as a ________ _______ on the petridish
Clear spot
Plaque assay tells us about _____ _____ and measures ______ ______.
Live bacteria, viable bacteria
Direct microscopic count of bacteria or viruses requires…..
Electron microscope
All microbes have _______ _______ conditions, by altering those conditions one can control the ________.
Growth conditions, growth
Psychro- prefix means
Cool or cold
Name the four subdivisions of microbial growth as far as temperature is concerned.
Cold to hot Psychrophiles Mesophiles Thermophiles Hyperthermophiles
Microbes that make human sick generally are…
Mesophiles
________ (deli meat) causes diarrhea or miscarriage of a child for a woman.
Listeria
Hyperthermophiles are typically ________ and live in volcanic vents at the bottom of the ocean.
Archea bacteria
________ have less saturated fatty acids ________ have more saturated fatty acids.
Psychrophiles, hyperthermophiles
What type of ocean food is bacterial overloaded
Shelfish or filter feaders