Cells and proteins - 1 Flashcards
What is a linear dilution?
consists of a range if dilutions that differ by an equal interval
how are measurement errors reduced in a linear dilution?
each concentration is made individually so errors are reduced to only one concentration
what is a log dilution?
range of dilutions that differ by a constant proportion
how is a log dilution made up
each dilution solution is used as stock for the next dilution
what is a colorimeter used for?
used to measure:
- the concentration of a pigment in a solution
- turbity of liquid
- density of cells in a culture
what does a colorimeter record?
how much light is absorbed by a sample
what is a standard curve used for?
to find an unknown concentration
what is the purpose of a buffer?
to keep the pH of a solution at a nearly constant value
what is centrifugation?
method for separating materials in suspension according to their density
what is the liquid fraction of a tube called after centrifugation?
supernatant
what technique is used to separate amino acids according to their solubility?
paper and TLC chromatography
what is protein electrophoresis?
the use of a current flowing through a buffer to separate proteins
what factors affect the rate of protein electrophoresis?
size and charge
when does a protein have a net neutral charge?
at its isoelectric point
what are antibodies?
naturally produced by white blood cells which targets microbes or other foreign cells for destruction
what are antibodies shaped specifically to?
the antigen on the cell
what is an antibody technique used for?
used for detection and identification of specific proteins
what is utilised in antibody techniques?
the ability of antibodies to bind to a specific antigens
what is a polyclonal antibody?
a serum made with many different antibodies against an antigen
what is immunohistochemical staining used for?
used to detect specific antigens in cells based on an antigen-antibody reaction
what is protein blotting?
when different types of antibodies are blotted onto gel with proteins
what produces antibodies?
B lymphocytes
what is an immunoassay technique such as an ELISA used for?
used for diagnosis and detection of disease
what is involved in an immunoassay?
- use of monoclonal antibodies that have an enzyme attached
- a reporter enzyme catalyses a colour change when an antigen interaction is present
what are monoclonal antibodies?
supply of antibodies that are identical and will bind to the exact same feature of the antigen
when making monoclonal antibodies, what fuses the B lymphocytes and myeloma cells together?
polyethylene glycol
what are produced when B lymphocytes and myeloma cells fuse together?
hybridomas
what is a cell culture?
when cells are grown under aseptic techniques
what is a benefit of a cell culture?
can produce many genetically identical clones of an initial cell sample
why must aseptic techniques be followed?
to help prevent contamination
state some aseptic techniques
- wearing a lab coat
- washing hands
- using an autoclave
- using a Bunsen burner to sterilise wired loops and prevent air borne organisms
what nutrients are required to grow mammalian cells?
- glucose
- growth factors, e.g - foetal bovine serum
- vitamins
- salts
- amino acids
what four steps are involved in the culturing of mammalian cells?
- adhesion
- spreading
- divison
- confluence
why are cancer (myeloma) cells good for research?
immortal and so unlimited life span
what two main methods are used for plant tissue culture?
explants and hybridisation
what is an explant?
small pieces of plant tissue that are placed on a solid medium
what is a haemocytomter?
a graduated micro slide used to count cell density
