A microorganism, esp. a bacterium causing disease or fermentation
Bacterial and Archaea
One type of bacterium growing separated from all others
A common technique for separating bacteria from one another.
in the 1880's developed a most of the equipment and media but also the aseptic techniques his contribution to the science to microbiolgy can not be overstimated.
to tansfer bacteria from a broth culture to an agar surace in a Petri plate. used whenever we transferring a liquid.
used when we transerring bacteria from a solid media.
any procedure that applies colored chemicals called dyes to specimens.
colored compounds related to or derived from the common organic solvent benzene.
1) basic (cationic)(+)
2) acid (anionic) (-)
What are the two staining techniue?
1) Postive stain most procedures involve (dye sticks to cells and gives them color)
2) Negative stain dye does not stick to specimen but dries around its outer boundary. (forming a silhouette Nigrosin(blue-black)& India ink(a black suspension of carbon particles) most common used (-) stain.
a color-bearing ion
carry a (+) chromophre & are atttracted to (-) cell comaponets (nucleic acids & protien. B/c bacteria contain large amounts of (-) charged substances, they stain readily with basic dyes (methylene bule, crystal violet,fuchsin & safranin.
classified as simple, differential or structrual
*require only a single dye & uncomplicated procdures
*cause all cells in a smear to appear more or less same color. regardless of type but they can still reveal bacterial charactersic such as shap, size & arrangement.
use two different-colored dyes called primary dye & counterstain to distinquish b/n cell types or parts (more complex)
an effective differential stain uses of contrasting color to clearly emphasize differences b/n 2 cell parts. common combinations are red & purple, red & green, or pink & blue. Also pinpoint other characterstics i.e size, shape, & arrangement of cells. eg. gram, acid-fast, & endospore stains.N.b some staining techniques (spore & capsule) fall into more than one category.
Hans Christian Gram
developer of Gram staining.
like the G stain, is important diagnostic stain that differentaites acid-fast bacteria (pink) from non acid-fast bacteria (blue). originated as a specific method to detect Mycobacterium tuberculosis in specimens
Endospore stain (spore stain)
smililar to the acide-fast method in that a dye is forced by heat into resistant survival cells called spores or endospores.
developed to distinquish b/n spores & the vegetative cells
can also be a practical aid in diagonsing infection & in guiding drug treatment. eg. gram staining of fresh unrine or throat specimen can help pinpoint the possible cause of infection.
G stain remains an important & unbeatable first tool in diagonosis.
the implantation of microorganisms into or upon culture media .
the observable growth that later appears in or on the medium.
mound of cells