Unit 1 - Topic 1 - Laboratory Techniques for Biologists - Section F - Aseptic technique and cell culture Flashcards
What does aseptic technique do
Eliminates unwanted microbial contaminants when culturing micro-organisms or cells
What does aseptic technique involve
The sterilisation of equipment and culture media by heat or chemical means and subsequent exclusion of microbial contaminants.
How is a microbial culture started
Using an inoculum of microbial cells on an agar medium, or in a broth with suitable nutrients
What do culture media do
promote the growth of specific types of cells and microbes
What are animal cells grown in and how do these effect the cell
Medium containing growth factors from serum. Growth factors are proteins that promote cell growth and proliferation. Growth factors are essential for the culture of most animal cells.
What is the difference between primary cell lines and tumour cell lines in culture
Primary cell lines can divide a limited number of times, whereas tumour cell lines can perform unlimited divisions
What does plating out a liquid microbial culture on solid media allow
The number of colony-forming units to be counted and the density of cells in the culture estimated
What is often need to achieve a suitable colony count
Serial dilution
What are haemocytometers used for
To estimate cell numbers in a liquid culture
What does vital staining do
Vital staining is required to identify and count viable cells
