Lab Quiz 1 Flashcards
What is the binomial system?
the method of naming microorganisms that combines the genus name and the species epithet
What properties of microorganisms lead to the rigid requirements of handling them?
they are extremely small, metabolize rapidly, and reach large numbers in a short time period
What is a pure culture?
culture in which each cell is a direct descendant of a single cell from a culture containing cells of only one species
What is prodigiosin?
the pigment in S. marcescens that causes it to be deep-red
(more/less) light is needed at higher magnification than lower magnifications
more
What is resolving power?
degree of definition of the fine structure of the material being observed (ability to separate 2 continuous objects)
What is refractive index?
the degree to which light bends through a medium
What are the three major parts of flagellum?
basal body, hook, and filament
What is the basal body?
a rod and a series of stabilizing rings that imparts rotation (motor of the flagellum)
What is the hook?
curved, flexible part extending from the basal body
What is the filament?
End of the flagellum, part that rotates
What is a peritrichous bacterium?
has flagella around the entire cell
What is a lophotrichous bacterium?
has flagella at one or both ends of the cell
What is a monotrichous bacterium?
has 1 flagella at one pole of the cell
What is a amphitrichous bacterium?
has 2 flagella, one at each end of the cell
What part of the flagella is in the cell envelope?
basal body
What part of the flagella is at the cell-surface?
hook
What part of the flagella extends into the environment?
filament
What is dark field microscopy used to observe?
living unstained microorganisms; examining very thin and distinctly shaped bacteria
What is phase-contrast microscopy used to observe?
living unstained cells against a background of similar optical density; bacteria motility, and bacterial structures like endospores, mircocompartments, and storage inclusions
What are 2 techniques often used to isolate a microorganism from a culture medium?
streak plate method and drop-dilution
What is a culture medium?
A medium that has favorable growth conditions for a particular type of microbe
What is agar?
a complex polysaccharide that is used as a solidifying agent in preparation of culture media
