Terms in this set (89)
In vitro means?
in the lab
What are some different factors that affect microbial growth?
nutrition, moisture, temperature, pH, salinity
For microbial growth where do the microbes get their energy from?
____________ are microorganisms that grow best at high temperatures
What are thermophiles?
microorganisms that grow best at high temperatures
__________ are microbes that grow best at moderate temperatures
What are mesophiles?
microorganisms that grow best at moderate temperatures
_____________ prefer cold temperatures (deep ocean water for example)
____________ organisms prefer warm temperatures but can even endure very cold or even freezing temperatures
What are psychrophiles?
microorganisms that prefer cold temperatures
What are psychroduric organisms?
microorganisms that prefer warm temps, but can withstand freezing temperatures
What pH does most microorganisms prefer?
neural or slightly alkaline
What are acidophiles?
microorganisms that prefer a more acidic pH
What is the name of microorganisms that prefer a slightly more acidic environment?
What are alkaliphiles?
microorganisms that prefer a more basic pH
What is the name of microorganisms that prefer a slightly more basic environment?
What is the pressure that is exerted on a cell membrane by solutions both inside and outside the cell?
What is osmotic pressure?
the pressure exerted on the cell membrane by solutions inside and outside the cell
What is the movement of a solvent, through a permeable membrane, from a lower concentration of solutes to a higher concentration of solutes?
What is osmosis?
the movement of solutes from a lower concentration to a higher concentration
What is a solute?
what is doing the dissolving
When the concentration of solutes in the external environment of a cell is greater than that of solutes inside the cell is known as what type of solution?
What is plasmolysis?
condition where the cell membrane and cytoplasm shrinks away from the cell wall
When the concentration of solutes outside a cell is less than that of solutes inside the cell is known as what type of solution?
Organisms that prefer to live in salty environments are called what?
halophiles or halophilic organisms
What are organisms that do not prefer to live in salty environments but are capable of surviving there?
What are piezophiles?
microbes that can survive in high atmospheric pressure
Microbes that prefer the same atmosphere that humans do are called what?
What are obligate aerobes?
microorganisms that prefer the same atmosphere as humans
Microbes that require reduced concentrations of oxygen are known as what?
What are microaerophiles?
microorganisms that require a reduced concentration of oxygen
Microorganisms that are killed by the presence of oxygen are known as what?
What are obligate anaerobes?
microorganisms that are killed when oxygen is present
Microorganisms that require increased concentrations of carbon dioxide are known as what?
What are capnophiles?
microbes that require an increased concentration of carbon dioxide
Bacterial growth refers to?
the increase in the number of organisms NOT their size
How does bacteria divide?
The time it takes for one cell to become two cells is called the?
Culture media prepared in the lab are referred to as __________ or _________ media
artificial or synthetic
What type of medium is one in which all the ingredients are known?
chemically defined medium
What is chemically defined medium?
one in which all the ingredients are known
What type of medium is a broth or solid containing a rich supply of special nutrients that promote the growth of fastidious organisms?
What is enriched medium?
one that is a broth or solid that is rich in nutrients for fussy organisms
What type of medium has added inhibitors that discourage growth of certain organisms while allowing the growth of a desired organisms?
What is selective medium?
one that has inhibitors to inhibit the growth of certain organisms, but allowing growth of the desired organism
What type of medium permits the differentiation of organisms that grow on the medium?
What is differential medium?
it permits the differentiation of organisms (usually a color change)
What is a popular liquid medium in bacteriology laboratories; supports the growth of all categories of bacteria. What is the name of this liquid medium?
___________ involves adding a portion of a specimen to the medium
How is inoculation accomplished?
by using a sterile inoculating loop
What are the three different types of incubators?
CO2 incubator, non-CO2 incubator, and an anaerobic incubator
What is used to determine growth by measuring the turbidity of the medium?
What is turbidity?
the cloudiness of the medium
What is used to determine the number of viable bacteria in a liquid sample?
viable plate count
What is a spectrophometer?
used to determine the growth of bacteria by measuring the turbididty
What is a viable plate count?
used to determine the number of viable bacteria in a liquid sample
Growing a pure culture of the organism in a liquid medium at a constant temperature is known as?
bacterial population growth curve
________ _____________ pathogens are microbes that can survive and multiply only only within living cell
What are obligate intracelluar pathogens?
pathogens that can only survive and multiply within living cells
Obligate intracellular pathogens include _______ and two groups of gram ________ ________
viruses, negative bacteria
What is the complete destruction of all microbes, including cell, spores, and viruses?
What is sterilization?
the complete destruction of all microbes
What is the destruction or removal of pathogens from nonliving objects by physical or chemical methods?
What is disinfection?
the destruction or removal of pathogens from nonliving objects
What does the suffix -cide or -cidal refer to?
What are chemicals that kill microbes?
biocidal agents, germicidal agents, and microbial agents
Sporicidal agents kill
Fungicidal agents kill
fungi, and fungal spores
Algicidal agents kill
Viricidal agents kill
An agent is a drug or chemical that inhibits growth and reproduction of microbes?
What is mirobistatic agent?
a drug or chemical that inhibits the growth and reproduction of microbes
An agent that specifically inhibits that metabolism and reproduction of bacteria
What is bacteriostatic?
an agent that inhibits the metabolism and reproduction of bacteria
This is a process that combines dehydration and freezing?
What is lyophilization?
combines dehydration and freezing
This refers to the presence of pathogens in blood or tissues
What is sepsis?
the presence of pathogens in the blood and tissues
Refers to the absence of pathogens in the blood or tissues?
What is asepsis?
the absence of pathogens in the blood or tissues
What is the prevention of infection called?
What is antisepsis?
the prevention of infection
What are the different types of heat?
dry and moist
What are the two factors that determine the effectiveness of heat for sterilization?
temperature and time
The lowest temperature that will kill all of the organisms in a standardized pure culture within a specified time?
thermal death point
What is the thermal death point?
the lowest temperature that will kill all organisms in a standard pure culture in a specific amount of time
What are the different physical methods to inhibit microbial growth?
cold, desiccation, radiation, ultrasonic waves, filters, gaseous atmosphere
Many dried microorganisms remain viable but cannot reproduce is known as?
These can be used safely on human tissues to reduce the number of organisms on the surface of the skin