Exam II: Microbial Growth Flashcards
What are the effects of mitosis and meiosis in regards to microbe growth?
There is no mitosis or meiosis involved in microbe growth
Why is it important to understand microbial growth? (2 reasons)
Infection control
Growth of industrial/biotech organisms
What is an example of why it would be beneficial to grow industrial/biotech organisms?
Antibiotics
What 3 chemical requirements must be present for microbial growth?
Water
Elements (CHOPSN)
Trace elements
Why are trace elements important for microbial growth?
They influence enzymatic activity for growth to occur
What are additional growth requirements for more complex (festidious) organisms (in addition to the basic 3)?
Source of energy (glucose)
Vitamins (coenzymes)
Some amino acids (purines, pyrimidines)
What is the name of an organism that is a “self feeder” for its carbon source?
Autotroph
What is the name of an organism that is an “other feeder” for its carbon source?
Heterotroph
Where do autotrophs get their carbon from? What are they also known as>
Gets carbon from CO2. “Carbon fixers”
What are 2 types of organisms in relation to what their energy source is?
Phototroph
Chemotroph
Where do phototrophs get their energy from?
Sunlight
Where do chemotrophs get their energy from?
Any other organic source
What is the odd one out (think: Deep Sea!)
Where do they get their carbon and energy from?
Lithotrophs
Carbon and energy are both from inorganic molecules (eg. sulfur vents)
What type of organism is a decomposer, feeding off dead organisms?
Saprobe
What type of organism is a pathogen, living off of a living host?
Parasite
What action do water molecules always have on solutes?
Water is always trying to dilute solutes. Water goes where solutes are higher.
What type of circumstance demonstrates no water movement (same solutes inside and outside)
Isotonic
What type of circumstance demonstrates a solution where there are more solutes outside the cell?
Hypertonic
What type of circumstance demonstrates a solution where there are less solutes outside of the cell?
Hypotonic
What occurs with the cell in a hypotonic solution?
The cell bursts (Water enters the cell)
What occurs with the cell in a hypertonic solution?
The cell shrivels (Water leaving the cell)
Which two forms of molecule movement (nutrients and substances) require NO energy?
Passive diffusion
Facilitated diffusion
How does active transport work?
Requires energy. Gradient low to high.
Which type of molecular movement uses a concentration gradient to go from high to low, and sometimes uses a protein gate?
Facilitated diffusion
What type of molecular movement uses osmosis, with a concentration gradient from high to low.
Passive diffusion
What type of molecular movement happens as a result of change in chemical makeup, causing lower to go to higher?
Group translocation
What type of molecular movement is used for larger molecules, liquids, or solids?
Bulk transport
Endocytosis, phagocytosis, and pinocytosis are examples of what action of molecular movement?
Bulk transport
Which organisms are cold loving?
Psycrophiles
What organisms are heat loving? What is a general minimum temperature requirement for this organism?
Thermophiles. 55’C+
What organisms are moderate temperature loving, and most common to humans? What is their optimum growth temp?
Mesophiles. 37’C
What happens when the temperature increases above the maximum temp for the organism?
Death occurs due to enzyme inactivation
What temperature slows or stops growth for most organisms?
40’F (5’C)
What is the term when something must have something
Obligate
What type of organism requires O2?
Obligate aerobes
What type of organism can use 02, but can also grow without it?
Facultative anaerobes
What type of organism cannot tolerate O2, and will die in its presence?
Obligate anaerobes
What type of organism does not use O2, but can still grow when it is present (different from facultative anaerobes)?
Aerotolerant
What type of organism requires O2, but will only grow in concentrations lower than atmospheric levels?
Microaerophiles
What type of organism prefers higher CO2 concentrations (5-10%)? Where is it common to find these organisms?
Capnophiles. Commonly found in mouth (from exhalation of CO2)
What is the name of the lab substance that is specially formulated to have an O2 gradient in the test tube which it is being used in?
Thioglycolate broth
How does a Brewer’s Jar work in a lab?
Gas pack causes H2O–>H2 + CO2.
Takes all CO2 out of the environment (creates anaerobic environment)
How does a Candle Jar work in a lab?
Creates a microaerophilic and capnophilic environment. Candle burns most of the O2, leaving a high CO2, low O2 environment.
What pH do most bacteria prefer to live in?
6.5 - 7.5 (similar to humans)
What type of conditions are a good preservative for pickles, sauerkraut, and cheeses, and what is the general pH in these conditions? What types of organisms can live there?
Acidic
<4 pH
Acidophiles
What is an example of an organism that can survive the low pH of the stomach (appx pH=1)? What is a common health effect of this organism?
Helicobacter pylori
Chronic ulcers
What is a term for a close nutritional relationship in regards to organisms?
Symbiotic
What kind of ecological association exists when one organism benefits without harm to the other, such as with a clown fish protected by a sea anemone?
Commensalism
What kind of ecological association exists when both organisms benefit from each other, such as with lithotrophic organisms in the digestive tracts of tube worms, which convert chemicals into sugar/nutrients for the benefit of both organisms?
Mutualism
What kind of ecological association exists when a host is harmed, while the organism benefits? What is a common example of such a relationship?
Parasitism. Ticks
What is the primary method that bacteria use to divide?
Binary fission
In what phase of growth are new enzymes being made in response to a new medium?
Lag phase
In what phase of growth is where exponential growth occurs, and is desired for the production of products?
Log phase
In what phase of growth when no nutrients are added, therefore nutrients are limited and waste products are becoming toxic?
Stationary phase
In which phase does death exceed division?
Death phase
Which phase would occur if a sample were to be left in an incubator with no added nutrients?
Stationary phase
In which phase is an organism most sensitive to drugs or radiation?
Log phase
A hemocytometer uses a ___ for measuring growth
Grid
Plating uses ___ for measuring growth
Dilution of samples
A hemocytometer and plating are examples of what kind of method for measuring?
Direct methods
What method of measurement depends on the use of a spectrometer, and the passage of light through a substance?
Turbidity
How are enzymatic activities used to measure growth in an organism?
Measures gas or protein output (indicates metabolic activity)
Using a spectrometer to measure light passage, and using enzymatic activity measurement, are examples of what kind of method for measuring?
Indirect methods
