Biology - Tools and techniques of the biotechnologist
Tools and techniques of the biotechnologist
This resource covers a number of tools and techniques used by
biotechnologists. Let's begin with gel electrophoresis.
In gel electrophoresis the mixture of DNA [1] fragments and a stain are
placed in wells in a slab of agar gel which has electrodes at each end to
create an electric field.
As DNA molecules are negatively charged (because of the phosphate groups
of the nucleotides), [2] they move towards the positive end of the gel.
* As the smaller fragments move faster than the larger ones, the
fragments separate
* The size of each fragment and therefore the number of bases [3] in each
fragment, can be calculated by comparing the distance moved against
fragments of known length
* The DNA segment, which could be a gene, has been identified. This
technique does not identify the actual sequence of bases.
