Term
What substances can damage the plasma membrane? |
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Definition
alcohol
detergent
polymyxin antibiotics |
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Term
Why is the plasma membrane a good target for antibiotics? |
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Definition
- disrupts the transport of substances across the membrane
- leakage causes cell death
- disrupts the electronic transport chain which produces ATP
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Term
How do salty foods prevent the growth of bacteria?
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Definition
Hypertonic environments, the cell shrinks and water moves out. |
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Term
What antibiotic/substances can damage Gram-positive cells? |
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Definition
- penicillin
- lysozyme
- detergents
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Term
What antibiotic/substances can damage Gram-negative cells?
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Definition
- streptomycin
- chloramphenicol
- tetracycline
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Term
Which microscope can see internal structures of a cell and needs ultrathin sections so electrons can pass through the specimen? |
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Definition
Transmission Electron Microscope |
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Term
What microscope enhances diffraction of the light that passes through a live specimen to see the internal structures of cells with out stain? |
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Definition
Phase-contrast microscope |
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Term
What microscope is used to stuy surface features of a specimen? |
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Definition
Scanning electron Microscope |
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Term
What microscope uses visible light to see a specimen against a bright background and uses stains to create contrast? |
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Definition
compound light microscope |
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Term
What microscope uses UV light, flourescent stains and antibodies to ake a specimen glow, and allows rapid detection of pathogens in tissues? |
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Definition
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Term
What microscope has a special condenser that blocks most light to see the outline of a live specimen with out staining? |
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Definition
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Term
What is the ability of lenses to distinguish two points? |
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Definition
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Term
What is the composition and function of the plasma membrane for a prokaryote?
Eucaryote? |
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Definition
Prokaryote- composition: made of phospholipids and proteins
function: permeability, makes ATP, Transportation
Eukaryote- composition: Phospholipid bilayer, sterols
Funtion: transportation |
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Term
What is the comopsition and function of the cell wall of a prokaryote?
eukayote?
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Definition
Prokaryote- composition: peptidoglycan
Function: protection
Eukaryote- no cell walls |
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Term
What is the funtion and composition of ribosomes in a eukaryote?
prokaryote? |
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Definition
Both: function: protein synthesis
composition: protein |
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Term
What is the composition and function of chromosomes in a prokaryote?
eukaryote? |
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Definition
Prokaryote- composition: nucleic acids (DNA) 1 chromosome
Function: storage of information
Eukaryote- composition: 46 DNA
function: storage of information
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Term
In what ways do eukaryotes and prokaryotes preform cell division? |
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Definition
Prokaryotes: binary fission
Eukaryotes: meiosis and mitosis |
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Term
What is the optimum temp for Mesophiles? psychrophiles? psychrotrophs? Thermophiles? hyperthermophiles?
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Definition
in order:
37 C
13 C
23 C
62 C
93 C |
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Term
What is the danger zone for bacteria where some may produce toxins? |
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Definition
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Term
What do microbes need to make organic molecules ot form their cell structures? What are these organic molecules? |
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Definition
Carbon
Carbohydrates, proteins, lipids, nucleic acids |
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Term
What element do microbes need as a source of energy? |
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Definition
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Term
What element do microbes need to make proteins and nucleic acids besides carbon? |
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Definition
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Term
How do microbes aquire nitrogen? |
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Definition
protein sources (food)
Nitrogen fixing bacteria can get nitrogen from the atmosphere |
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Term
What important role does sulfur play in microbial growth? |
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Definition
its needed to make some amino acids and vitamins |
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Term
What element do microbes need to make nucleic acids and the bilayer of plasma membranes. |
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Definition
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Term
What element(s) do microbes need to make cofactors of enzymes? |
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Definition
trace elements, mineral elements |
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Term
What are organic growth factors? Give an example of some. |
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Definition
essential organic compounds from the environment
eg. vitamins, amino acids, and bases of DNA and RNA |
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Term
What pH do bacteria like? |
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Definition
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Term
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Definition
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Term
Nutrients prepared to grow microbes
eg. nutrient agar |
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Definition
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Term
Contains no living microbes |
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Definition
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Term
microbe introduced into a culture medium to initate growth |
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Definition
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Term
microbes growing in/on a culture medium |
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Definition
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Term
contains only one species or strain |
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Definition
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Term
a visible mass of microbial cells that arose from a single cell, spore, or a group of attached cells |
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Definition
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Term
what does preserbing bacterial cultures for a long term do to bacteria? How long does this last?
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Definition
totaly stops metabolism
years |
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Term
What does preserving bacterial cultures for a short term do to bacteria? How long does this last? |
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Definition
slows down metabolism
3-4 months |
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Term
name and define 2 long term ways to preserve bacterial cultures and the temperature they are stored at |
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Definition
Deep-freezing - in liquid nitrogen -50 to -95 C
Lyophilization- freeze drying; dehydrate in a vacuume then freeze -54 to -72 C |
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Term
Name 2 methods of obtaining a pure culture |
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Definition
pour plate method
streak plate method |
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Term
Which culture media has a chemical composition that varies slightly per batch and is routinely used to grow many kinds of bacteria?
eg. nutrient agar |
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Definition
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Term
which culture media are we using where the exact chemical composition is known? |
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Definition
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Term
Which culture media suppresses the growth of uneanted microbes and encourages he growth of the desired microbe?
eg. Sabourand agar |
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Definition
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Term
Which culture media makes it easier to distinguish colonies of desired microbes? |
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Definition
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Term
which culture media encourages the growth of the desired microbe? |
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Definition
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Term
What is the time for a cell to divide and its population to double called? |
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Definition
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Term
Which phase of the bacterial growth curve is intense cellular activity and no cell division? |
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Definition
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Term
Which phase of the bacterial growth curve used to determine generation time, is most effective to treat infections, and is under optimum conditions? |
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Definition
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Term
Which phase of the bacterial growth curve is slower growth and has new cells and dying cells? |
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Definition
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Term
which phase of the bacterial growth curve shows a logarithmic decline where dying cells exceed new cells formed? |
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Definition
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Term
Name the 4 phases of the bacterial growth curve. |
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Definition
lag phase
log phase
stationary phase
death phase |
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Term
Name the 4 direct methods of measuring microbial growth. |
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Definition
plate count
most probable number (mpn)
direct microscope count
filtration |
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Term
Which method of measuring microbial growth is a common method for estimating the number of bacteria in a sample, uses colony forming units (CFU), and assumes that each bacterial cell grows in a single colony? |
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Definition
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Term
What are the advantages and disadvantages of a plate count in measuring microbial growth? |
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Definition
A: counts only the number of living viable cells
D: -need a lot of materials to preform serial dilutions of a sample
-requires time for incubation |
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Term
Which method of measuring microbial growth is a statistical estimation of a bacterial count and is used when microbes wont grow on solid media or will only grow in liquid differential media. |
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Definition
Most Probale Number (MPN) |
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Term
which method in measuring microbial growth uses a special slide that can hold a measured volume of bacterial suspension? |
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Definition
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Term
What are the advantages and disadvantages of the direct microscope count method in measuring microbial growth? |
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Definition
A: a fast way of counting the number of cells
D: -requires a high concenration of cells in a sample
-does not work if the baceria are motile
-counts living and dead cells |
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Term
which method in measuring microbial gowth is where bacteria are sieved out onto the surface of a membrane filter then transferred to a culture medium and the CFUs are counted? |
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Definition
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Term
Which method in measuring microbial growth is a useful method when the bacterial count is low? |
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Definition
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Term
Name the 3 indirect methods of measuring microbial growth. |
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Definition
turbidity
metabolic activity
dry weight |
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Term
Which method for measuring microbial growth measures the level of cloudiness and uses an instrument that measures he amount of light that passes through a suspension of cells? What is that instrument called? |
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Definition
Turbidity
spectrophotometer |
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Term
Which method in measuring microbial growth measures he amount of metaolic profucts such as acid, gas, and enzyme production? |
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Definition
Metabolic Activity method |
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Term
Which method in measuring microbial growth is used for filamentous organisms, like fungi and algae, that can be grown, dried, and weighed? |
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Definition
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Term
What is the structure in a bacteria that is small, circular, self replicating DNA that may contain a few genes? |
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Definition
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Term
What type of media is a Mannitol salt agar? |
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Definition
selective and differential |
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Term
what type of medium is a blood agar? |
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Definition
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