CHAPTER 3 GUIDE - terms Flashcards
Inoculation
The implantation of microorganisms into or upon culture media.
Incubation
To isolate a sample culture in a temperature-controlled environment to encourage growth.
Isolation
The separation of microbial cells by serial dilution or mechanical dispersion on solid media to create discrete colonies.
Pure culture
A container growing a single species of microbe whose identity is known.
Microscopy
Science that studies structure, magnification, lenses, and techniques related to use of a microscope.
Magnification
The ability to make objects appear enlarged.
Resolution
The capacity of a microscope lens system to accurately distinguish between two separate entities that lie close to each other
Condenser
A special lens that converges or focuses the rays of light to a single point on the object.
Numerical aperture (NA)
In Microscopy, a measure of the light passing from the object and into the objective to maximize optical clarity and resolution.
Wet mount
It consists of a drop or two of the culture placed on a slide and overlaid with a cover glass.
Positive stain
Technique in which dye affixes to a specimen and imparts color to it. It takes advantage of the ready binding of bacterial cells to dyes.
Negative stain
A staining technique that renders the background opaque or colored and leaves the object unstained so that it is outlined as a colorless area.
Simple stain
Type of positive staining technique that uses a single dye to add color to cells so that they are easier to see. This technique tends to color all cells the same color.
Differential stain
A technique that utilizes two dyes to distinguish between different microbial groups or cell parts by color reaction.
Hans Christian Gram
He discovered a staining technique that could be used to make bacteria in infectious specimens more visible.
Gram-positive
A color reaction of the cells which stained purple.
Gram-negative
A color reaction of the cells which stained red.
Acid-fast stain
It is another commonly used differential stain. This stain originated as a specific method to detect Mycobacterium tuberculosis in specimens
capsule stain
It is a method of observing the microbial capsule, an unstructured protective layer surrounding the cells of some bacteria and fungi.
Culture
The visible accumulation of microorganisms in or on a nutrient medium. Also, the propagation of microorganisms with various media.
Subculture
To make a second-generation culture from a well-established colony of organisms.
Medium/media
A nutrient used to grow organisms outside of their natural habitats.
Colony
A growth of bacteria cell on a surface.
Morphology
The study of organismic structure.
