KA1: laboratory techniques for biologists: aseptic technique and cell culture Flashcards
what does aseptic technique do?
eliminates unwanted microbial contaminants when culturing microorganisms or cells
what does aseptic technique involve?
-sterilisation of equipment and culture media by heat or chemical means
-exclusion of microbial contaminants
how can a microbial culture can be started?
-using an inoculum of microbial cells on an agar
medium
-in a broth with suitable nutrients
Many culture media exist that promote….
the growth of specific types of cells and microbes
what are animal cells grown in?
medium containing growth factors from serum
what are growth factors?
proteins that promote cell growth and proliferation
they’re essential for the culture of most animal cells
in culture, what is the difference between primary cell lines and tumour cell lines?
primary: can divide a limited number of times
tumour: can perform unlimited divisions
what does plating out of a liquid microbial culture on a solid media allow?
the number of colony-forming units to be counted and the density of cells in the culture estimated
what is serial dilution often needed for?
to achieve a suitable colony count
what is the main use of a haemocytometer?
estimating cell numbers in a liquid culture
what is vital staining required for?
to identify and count viable cells
