Classification 2.6 Flashcards
What is phylogenetics?
The study of the evolutionary history of groups of organisms.
What does a hominidae tree show?
It shows how recently species diverged from each other.
Why is it hard to define organisms?
Because you can’t always see there reproductive behaviour, because their extinct, reproduce asexually or it’s unethical to bread the two species.
What is DNA sequencing?
When the DNA of organisms can be directly compared by looking at the order of the bases in each. Closely related species will have a higher percentage of similarity. ( this method has led to new classification systems)
What is taxonomy?
The science of classification, it involves naming organisms and organising them into groups based on similarities and differences.
Outline the procedure for DNA hybridisation?
DNA from two different species is collected and separated into separate strands and mixed together. Where the base sequences of DNA are the same on both strands, hydrogen bonds will form, by specific base pairing. The more DNA bases that hybridise the more alike the DNA is.
The DNA is then heated to separate the strands again, similar DNA will have more hydrogen bonds and so a higher temp will be needed to overcome those bonds.
How are proteins compared?
Directly comparing Amino acid sequence.
Immunology comparisons - similar proteins will bind the same antibodies.
What is courtship?
Courtship is a behaviour carried out by organisms to attract a mate of the right species. It can anything from a series of displays to releasing chemicals.
