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Micro chapter 7 quiz

vocab
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An organism that can not grow without oxygen is a(n)
obligate aerobe
When it is important to count the number of cells, determine cell size and differentiate between dead and live cells a ___ is used.
flow cytometer
The production of antibiotics is a form of antagonism called
antibiosis
Archea as a group are not pathogens. This is because
Mammalian hosts do not meet their environmental requirements
Most of the dry weight of a microbial cell is from
organic compounds
An organism that uses CO2 for its carbon needs and sunlight for its energy needs would be called a/an
photoautotroph
In the viable plate count method, a measured sample of a culture is evenly spread across an agar surface and incubated. Each _____ represents one _____ from the sample.
colony
cell
Growth factors
Cannot be synthesized by the organism
Organisms that feed on dead organisms for nutrients are called
saprobes
An organism that grows slowly in the cold but has an optimum growth temperature of 32° C is called a(n)
facultative psycrophile
A barophile would grow best in
deep oceans
True or False: Most microorganisms on earth can only live and survive in habitats that are similar to human body conditions.
false
A microorganism that has an optimum growth temperature of 37° C, but can survive short exposure to high temperatures is called a(n)
thermoduric
True of False: Facilitated diffusion and active transport require a carrier protein to mediate the movement across the plasma membrane.
true
True or False: Bacteria have an average generation time of 24 hours.
false
Trueor False: Saprobes do not need a carbon source for growth and metabolism.
false
When whole cells or large molecules in solution are engulfed by a cell, this endocytosis is specifically termed
phagocytosis
True or False:





Transverse binary fission results in 4 daughter cells from 1 parent cell.
false
The term facultative refers to
The ability to exist in a wide range of conditions
Contractile vacuoles are
used to expel excess water from cells
Mediated transport of polar molecules and ions across the plasma membrane utilizes a _____ _____ that will bind to the substance effecting a conformational change that allows movement across the membrane.
protein carrier
Cultures of a bacterial species were incubated on the shelf of a refrigerator, out on a lab bench top, on the shelf of a 37° C incubator and on the shelf of a 50° C incubator. After incubation, there was no growth at 37° C and 50° C, slight growth out on the bench top and abundant growth at refrigeration. What term could be used for this species?
psychrophile
A microaerophile
Requires a small amount of oxygen but won't grow at normal atmospheric levels
True or False: Phosphorus is one of the major elements needed in larger quantities by microorganisms.
true
An organism with a temperature growth range of 45° C to 60° C would be called a(n)
thermophile
The term autotroph refers to an organism that:
Uses CO2 for its carbon source
True or False: Whether an organism is an autotroph or heterotroph depends on its source of nitrogen.
false
True or False: Whether an organism is an autotroph or heterotroph depends on its source of nitrogen.
false
Which of the following microorganisms would find hypotonic conditions most detrimental?
protozoa
Organisms called _____ live on or in the body of a host and cause some degree of harm.
pathogens
Human pathogens fall into the group
mesophiles
The term heterotroph refers to an organism that
must obtain organic comound for its cabon needs
In _____ conditions, the cell wall will help prevent the cell from bursting.
hypotonic
All of the following could find a location in or on body tissues suitable for growth except
psychrophiles
An organism that can exist in both oxygen and oxygen-less environments is a(n)
Facultative anaerobe
A microorganism that does not have catalase or superoxide dismutase would find it difficult to live in an environment with
oxygen
Halobacteria regulate osmotic pressure by
Absorbing salt from the environment
Calcium is required for bacteria because
It stabilizes the cell wall
A change in one partner in a close relationship that leads to a change in the other partner is
coevolution
A halophile would grow best in
salt lakes
Aerobic respiration is an example of
Chemoheterotrophy
The movement of substances from higher to lower concentration across a semi permeable membrane that must have a specific protein carrier but no energy expenditure is called
Facilitated diffusion
When microbes live independently but cooperate and share nutrients, it is called
synergism
True or False: A saprobe with a cell wall will utilize extracellular digestion.
true
Facilitated diffusion is limited by
Carrier proteins in the membrane
When microbes in close nutritional relationship and one benefits but the other is not harmed, it is called
commensalism
True or False: In a commensal relationship, the commensal benefits but the cohabitant is neither harmed nor benefited.
true
True or False: A Coulter counter can count viable cells as well as determine the size.
false
True or False: The direct cell count, using a cytometer, can calculate viable cell numbers from a sample.
false
The movement of molecules from an area of high concentration to an area of lower concentration is called
diffusion
True or False: Bacterial biofilms stimulate the immune system differently than planktonic bacteria.
true
The methanogens, producers of methane gas, require environments that
Are anaerobic with hydrogen gas and CO2
The E. coli that normally live in the human large intestines and produce vitamin K that the body uses would be best termed a _____ relationship.
mutualistic
True or False: Inorganic nitrogen must be converted to ammonia to be used by a cell.
true
True or False:Anaerobes can be cultured in a CO2 environment.
true
Which of the following is not a major element of a microbial cell?
copper
The phase of the bacterial growth curve in which newly inoculated cells are adjusting to their new environment, metabolizing but not growing is the
lag phase
True or False: Lithoautotrophs use inorganic nutrients for carbon and energy sources.
true
The movement of substances from lower to higher concentration across a semi permeable membrane that must have a specific protein carrier and cell expenditure of energy is called
active transport
True or False: Whether an organism is a phototroph or a chemotroph depends on its source of energy.
true
The type of photosynthesis that does not produce oxygen
occurs in purple or green sulfur bacteria
Microorganisms require small quantities of this nutrient for enzyme function and maintenance of protein structure
trace element
The term phototroph refers to an organism that
Gets energy from sunlight
True or False: The degree of turbidity in a broth culture correlates to the amount of cell growth.
true
Diffusion of water through a semi permeable membrane is called
osmosis
Bacteria living in a freshwater stream that are moved to salty seawater would
shrivel
True or False: A closed culture system is used to determine a population growth curve.
true
The toxic superoxide ion is converted to harmless oxygen by two enzymes
Superoxide dismutase and catalase
An organic nutrient that cannot be synthesized by the organism and must be provided is called a/an
growth factor
The time interval from parent cell to two new daughter cells is called the
generation time
Microorganisms require large quantities of this nutrient for use in cell structure and metabolism
macronutrient
The term obligate refers to
Existing in a very narrow niche
Nutrient absorption is mediated by the
cell membrane
What compound has the highest concentration in a cell?
H2O
The use of energy by a cell to enclose a substance in its membrane by forming a vacuole and engulfing it is called
endocytosis
An organism that cannot tolerate an oxygen environment is a(n)
obligate anaerobe
What type of media is used to demonstrate oxygen requirements of microbes?
thioglycollate
True or False: The time that it takes for a freshly inoculated agar culture to develop visible colonies is principally governed by that species' generation time.
true
The term chemotroph refers to an organism that
Gets energy by oxidizing chemical compounds
True or False: The majority of microbes live and grow in habitats between pH 7 and 9.
false
The phase of the bacterial growth curve in which the rate of multiplication equals the rate of cell death is the
stationary phase
True or False: After binary fission, daughter cells will differ genetically.
false
Which of the following require the cell to use ATP?
endocytosis
The phase of the bacterial growth curve that shows the maximum rate of cell division is the
log phase
An important mineral ion of the cytochrome pigments of cellular respiration is
iron
An important mineral ion that is a component of chloroplasts and stabilizer of membranes and ribosomes is
magnesium
True or False:





Planktonic bacteria are more susceptible to antibiotics as compared to biofilm microorganisms.
true
Cultures of a bacterial species were incubated out on the incubator shelf, in an anaerobic jar and in a candle jar. After incubation there was moderate growth of cultures in the candle and anaerobic jars, but heavy growth of the culture on the incubator shelf. This species is a/an
Facultative anaerobe
Microorganisms that live in severe habitats, such as very hot, acidic or salty environments, are called
Extremophiles
An organism that can use gaseous oxygen in metabolism and has the enzymes to process toxic oxygen products is a(n)
Aerobe
isotonic conditions means that
the environment is equal in solute concentration to the cell's internal environment.
passive transport definition
the cell does not expend extra energy for them to function
hypertonic conditions
environment is exposed to a higher solute concentration than its cytoplasm
hypotonic conditions
the solute concentration of the external environment is lower than that of the cell's internal environment
plasmolysis defintion
shrinkage of the protoplast away from the wall
true or false: norganic nitrogen must be converted to ammonia to be used by a cell.
true