Verified by Experts
selective media Media that encourages the growth of one species or group of species
while inhibiting others; MacConkey
differential media Allows for a specific metabolic activity of an organism to be detected
by visual inspection of growth of organism; MacConkey, sheep's blood agar
Ex: pH indicator, changing colors
liquid media Broth; becomes turbid as bacteria grow in numbers
semi-solid media Growth is seen going outwards in test tube
solid media Made with agar & broth, used in agar slant or petri dish
,non-selective media Media that supports the growth of most bacteria; sheep's blood agar,
trypticase soy agar, nutrient agar
resolution Ability to see two items that are close together as two separate & individual
objects
oil immersion Prevents refraction of light & increases resolution
magnification Total power of all lenses: ocular x objective
streak plate method Used to create spatial separation of individual cells; produce isolated
colonies on an agar plate
slide smear prep 1) Label slide
2) Place a small drop of sterile water on slide
3) Collect specimen
4) Roll swab onto water drop/slide
5) Dry on warming tray
, 6) Heat fixation (run it twice through flame)
simple stain One color to provide contrast; can reveal size, shape, & arrangement
negative stain Dye sticks to background, creating a silhouette; negative charged cells
repel negative charged dye
Ex: capsule stain
positive stain Dye sticks to specimen & gives it color
differential stain Allows for differentiation of different structures and/or characteristics of
certain bacterial species
Uses two different colored dyes: primary & counterstain
1) Gram stain
2) Acid-fast stain