5.4.U1 A clade is a group of organisms that have evolved from a common ancestor.
Define clade and cladistics.
5.4.U2 Evidence for which species are part of a clade can be obtained from the base sequences of a gene or the corresponding amino acid sequence of a protein.
Outline the relationship between time, evolutionary relationships and biological sequences (nitrogenous base or amino acid).
5.4.U3 Sequence differences accumulate gradually so there is a positive correlation between the number of differences between two species and the time since they diverged from a common ancestor.
Outline the use of a “molecular clock” to determine time since divergence between two species.
State the source of differences between biological sequences (nitrogenous base or amino acid).
5.4.U4 Traits can be analogous or homologous.
Contrast analogous and homologous traits.
State an example of analogous and homologous traits.
5.4.U5 Cladograms are tree diagrams that show the most probable sequence of divergence in clades.
Define cladogram and node.
Outline how computer programs analyze biological sequence data to create cladograms.
Identify members of clades given a cladogram.
5.4.U6 Evidence from cladistics has shown that classifications of some groups based on structure did not correspond with the evolutionary origins of a group or species.
Outline the role of technological advancements in the development of cladistics.
Explain why the development of cladistics lead to the reclassification of some species.
5.4.A1 Cladograms including human and other primates.
Interpret a cladogram depicting primate species.
5.4.A2 Reclassification of the figwort family using evidence from cladistics.
Outline the reason and evidence for the reclassification of the figwort family.
5.4.S1 Analysis of cladograms to deduce evolutionary relationships.
Analyze a cladogram to explain the evolutionary relationship between species.
Discuss the use of cladograms as hypotheses of evolutionary relationships.
5.4.NOS Falsification of theories with one theory being superseded by another- plant families have been reclassified as a result of evidence from cladistics.
Outline the reason why biological theories may change with time.
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