Practise comparing aligned DNA base sequences, counting differences and using molecular classification trees to judge how closely organisms are related.
DNA can be extracted from the webs of spiders. This DNA can be used to identify the species of spider that made the web, and the species of prey caught in the web.
Explain how DNA extracted from spider webs can be used to identify different species.
identification can be done using: base, sequences / order / pattern, in DNA / genes ; each species, has unique / AW, DNA / genes ;
idea that compare with, reference DNA / base sequences / genes, of known species ;
idea that if a match with DNA from known species then DNA is from that species OR closely related species have fewer differences in their, base sequences / DNA / genes ;
AVP ; e.g. any technique involved in DNA analysis