Tools for lab Flashcards
Culture
To grow a microbe
Sample or group of microbes
Medium
nutrients for the growth of microbes
Inoculum
a small sample of microbes
Inoculation
a sample microbe is placed in media with a tool
Clinical Specimens
from the bodily fluids, discharges, anatomical sites, diseased tissue
Incubated
placed in a temperature-controlled area
Cultured Media uses
Flask, Petri dishes, and tubes
Media inoculated with
Needle, loops, swabs, pipes
Media Classified by
Physical state, chemical composition, and function(purpose)
Agar
complex polysaccharide from red algae; Solid at room temp Melts at 100 C holds moisture and nutrients Microorganisms cannot digest
Physical states of media
Liquid(Nutrient broth)
Solid that can be liquid( media has levels of agar)
Solid that cannot be converted to liquid
Semi-solid (media has low levels of agar)
Chemical Composition of Media:
Defined/ Synthetic
We know all the components of media chemical
Chemical Composition of Media:
Complex
One component of media is not precisely defined
Media Purpose/Function:
General-purpose media
Allow the growth of a broad spectrum of microbes
Media Purpose :
Enriched media
grow microbes that need special growth factors
Fastidious
microbes that must have special growth factors and complex nutrients
Selective media
can inhibit the growth of certain microbes but not inhibit the growth of other microbes
Differential media ;
changes you might see
show the visible differences in how microorganisms grow.
variation in colony size or color
media might change color
gas bubbles
Reducing medium
cystine will absorb O2 or slow the penetration of 02 in a medium.
Use when culture anaerobic bacteria
Carbohydrate fermentation media
has sugars that are fermented and converted to acids and a pH indicator to show this reaction
Transport media
used to maintain specimens that have to be held for a period of time before sent to a lab
Isolation
the single microbe is separated from other cells on a nutrient surface and form a colony
Colony
a mound of the same species of microbe from isolation
Streak plate method
a small drop of culture is spread over media with a loop in a pattern to thin out culture
this allows a single cell to grow into a colony
Loop dilution/ pour plate
the sample is inoculated multiple times in a cooled agar tube to dilute the number of cells in each tube.
end result is to have a volume of cells decreased so cells may have room to grow in colonies
Spread plate technique
the diluted sample is piped onto media and spread evenly
this will push cells into separate areas so they can form colonies
How are microbes identified
microscope metabolic features their nutrient needs enzyme presence genes
