Many modern biotechnologies are based on our growing understanding of gene structure and function. A range of DNA-based laboratory techniques are used to study individual genes, groups of genes and whole genomes.
What is DNA
(deoxyribonucleic acid) is contained in the of every . It is the main component of and is the material that transfers genetic characteristics from one generation to the next.
DNA needs to be released from the cell’s nucleus before it can be analysed.
DNA molecules extracted from a cell’s nucleus are very long and thin. are used to break up the DNA into fragments. These smaller fragments can then be size separated using . This is the beginning of many DNA-based experiments.
A DNA molecule actually has two strands of nucleotides that join together and wrap around each other to form a structure known as the.
The sugar-phosphate-nucleotides of DNA strands are represented by the letters G, A, T and C. Instructions or codes are ‘written’ in the sequence of the nucleotides. For example, a GATCCA sequence carries a different instruction to a GACCAT sequence.
Try the activity, Modelling DNA with your class.
Making multiple copies of DNA
Generating multiple copies of DNA or of a particular gene is an important first step in many biotechnology, science and forensic applications.
Related activity idea
This activity helps students conceptualise DNA by extracting it from tomatoes.