bio uni1

hazard

something that harm could be caused by

hazards in a lab

toxic/corrosive substances, heat/flammable substances, pathogenic organisms, mechanical equipment

risk

the likely hood of ham arising from a hazard

risk assesment

identifies hazards and gives appropriate controls to minimise the risks associated with them

linear dilution

dilutions differ by an equal interval, eg. 0.1, 02, 0.3

log dilution

dilutions differ by a constant proportion eg. 0.1, 0.01, 0.001,

standard currve

line of best fit used to estimate unknown values

buffer

a solution that resists changes in pH and is used to keep the pH of an experiment constant

colorimetry

used to determine the concentration of coloured solutions or the turbidity of a solution

turbidity

how cloudy a solution is, can be used to measure the amount of cells in liquid culture

centrifuge

separates a mixture by density

pellet

the more dense components of a mixture separated by centrifuge

super latent

where the less dense components remain when centrifuged

paper of thin layer chromatography

used to substances such as amino acids and sugars, is based on solubility, more soluble substances travel faster

affinity chromatography

separates mixtures of proteins by passing through a column containing specific receptors, is based on protein affinity

gel electrophoresis

used to separate proteins or nucleic acids by passing a charge through a gel matrix

Native gel electophoresis

separates proteins based on size, shape and charge

SDS page gel elctrophoresis

denatures proteins and gives them all a negative charge, so they are separated by size only

isoelectric point

the pH at which a protein has no net charge and will precipitate out of solution

IEP electrophoresis

gel elctrophorisis with a pH gradient where proteins precipitate out then they reach their IEP

immunoassy

a technique that uses antibodies linked to a chemical label to detect and identify specific proteins

monoclonal antibodies

stocks of antibodies with the same specificity

western blotting

after SDS page electrophoresis separated proteins are transferred to a solid medium and identified using immunoassay

bright field microscopy

uses light to view whole organisms, parts of organisms thin sections of tissue or single cells

florescence microscopy

uses specific florescent labels to visualise structures or molecules within cells

aseptic techniques

eliminate unwanted microbial contaminants when culturing microorganisms or cells

examples of aseptic technique

sterilisation of equipment and culture media by heat or chemicals, preventing cross contamination

microbial culture

method for growing microorganisms under controlled conditions

types of growth media

agar or broth with sufficient nutrients for growth

growth factors

proteins that promote cell growth and propagation and are needed for teh growth of animal cells

serum

how growth factors are provided for animal cells in culture

primary cell lines

cells that have a limited number of divisions when cultured

tumour cell lines

cells that have an unlimited number of divisions when cultured

heamocytometer

used to estimate the number of cells in a liquid culture

vital staining

stain that only colours dead cells allowing living cells to be counted

planting of liquid culture onto solid media

used to estimate the number of colony forming units in a liquid culture so cell density can be estimated