5.4 Flashcards
what is morphology?
the shape of something (like the shape of a bird beak)
what is anatomy?
the structures something has (like the number of petals on a flower)
what is cytology?
the structure or function of cells
what is phytochemistry?
analysis of special chemicals that plants make to defend themselves from insects
what is the chromosome number?
species with similar chromosome number are more likely to be closely related
what are molecular comparisons?
comparing proteins and DNA sequences between species
what is cladistics?
a system of classification that groups organisms together according to the characteristics that have evolved most recently
what does cladistics rely on?
knowing common ancestry.
what are primitive traits?
characteristics that have the same structure and function and evolved early on in the history of the organisms
what are derived traits?
characteristics that have the same structure and function but have evolved more recently
what is a clade?
a monophyletic group meaning a group of the most recent common ancestor of the group and all of its descendants
why are organisms placed in clades?
because they share characteristics developed from a common ancestor
how i DNA evidence for clades?
because all living things have DNA with the same four bases that code for making proteins using the same 20 amino acids, the only way to explain this is through common ancestor
what is phylogeny?
the study of the evolutionary past of a species
what is hybridization?
a test to see how many base sequences are shared between different species
what is the process of hybridization?
take one strand of DNA from species A
put it next to the complementary strand from species B
where the base pair connect there is a match
where they are repelled and do not connect there is a difference in the DNA sequence
what do more differences in the DNA sequences of two species mean?
means the longer it has been since their common ancestor diverged into new species
what does less differences in DNA sequencing mean?
the more recent their common ancestor
what are homologous traits?
a trait/structure that is derived from the same part of the common ancestor
what are analogus traits?
characteristics that may have the same function but they do not necessarily have the same structure and they are not derived from a common ancestor.
what are cladograms?
diagrams that show how different clades evolved from common ancestors.
what is circumscription?
whe branches of a clade need to be moved around to show a more consistent grouping with a common ancestor.
what is different between traditional classification and cladistics?
cladistics involves putting organisms into groups based on ancestry and evolution of shared characteristics.
