Aseptic techniques and cell culture Flashcards
Aseptic technique
eliminates unwanted microbial contaminants when culturing
micro-organisms or cells
A microbial culture
can be started using an inoculum of microbial cells on an agar medium,
or in a broth with suitable nutrients
Animal cells are grown in medium containing…
growth factors from serum
primary cell lines can divide…
a limited number of times
tumour cells
lines…
can perform unlimited divisions
Plating out of a liquid microbial culture on solid media allows…
the number of colony-forming
units to be counted and the density of cells in the culture estimated
Serial dilution is often needed to achieve…
a suitable colony count
Haemocytometer
good for estimating total cell count but not distinguishing between viable and dead cells.
Vital staining
required to identify viable cells and count them. Living cells do not take up the stain but dead cells do.
