DNA Technology
Biology: IB Diploma Higher Level, topic 13.3.3
Evolutionary Relationships
Advances in technology have led to the development of new techniques to help establish evolutionary relationships between species. These techniques include:
Genome sequencing
- The base sequences of organisms can be sequenced and compared to other organisms.
- The more similar the base sequences are between organisms, the more closely related the two organisms are.
- Genome sequencing has helped clarify evolutionary relationships (e.g. the relationship between skunks and weasels).
Amino acid sequencing
- The amino acids that make-up proteins in an organism can be sequenced and compared to other organisms.
- The more similar the amino acid sequences are between organisms, the more closely related they are.
- E.g. Cytochrome C is an electron carrier protein used in respiration (it is in many organisms). Comparing the amino acid sequence of cytochrome C between organisms clarifies evolutionary relationships.
Antibody-antigen interactions
- Species produce specific antibodies that recognise foreign proteins.
- An organism's antibodies can be isolated and mixed with another organism's proteins to see how many antigen-antibody complexes are formed.
- The more complexes that form, the more closely related the two organisms are.
Test yourself on DNA Technology
Which of the following statements about DNA technology are true?
Which of these is NOT a DNA technique that can be used to clarify evolutionary relationships?