Lab Test Flashcards
provides scientific names for organisms, describes them, preserves collections of them, provides classification for the organisms, keys for their identification, and data on their distributions, investigates their evolutionary histories, and considers their environmental adaptation
systematics
identifying, describing, naming, and grouping organisms in a hierarchical structure, does not directly infer ancestry
taxonomy
inferring groupings/relationships based on ancestry, often requires taxonomic descriptions/traits for inference
phylogenetics
a hypothesis of how taxa are related, represented as a branching tree
includes meaningful branch lengths, representing evolutionary distance or time
phylogeny
shows only relative relationships, branch lengths are arbitrary
cladogram
the name of a group of organisms
taxon
a branching point on a cladogram, represents the last common ancestor for all branches above/beyond the ____, corresponds to a particular taxonomic level or “clade”
node
a group of taxa that share a common ancestor
clade
a group of taxa composed only of a common ancestor and all of its descendants
Everything connected up from a node
monophyly (monophyletic)
a group of taxa composed of a common ancestor and NOT all of its descendants
paraphyly (paraphyletic)
a taxonomic group that includes members from different ancestral lineages
polyphyly (polyphyletic)
the group of related organisms under current study
ingroup
a closely related organism that doesn’t belong to the ingroup, used for comparison and rooting the tree
Always branches off first from the root, is NOT the ancestor
outgroup
an observable trait of an organism
character
ancestral character state
plesiomorphy
ancestral character state that is shared among taxa; inferred to be shared due to common ancestry
synplesiomorphy
same evolutionary origin, but different form/function
homologous traits
derived (new) character state
apomorphy
derived character state that only belongs to a single taxon
autapomorphy
derived character state that is shared among taxa
synapomorphy
ex: presence/absence of a character
character state
character state that has been independently gained/lost in separate lineages
homoplasy
similar function but different evolutionary origin
analogous traits
when faced with multiple hypotheses, select the one that makes the fewest assumptions
parsimony
when faced with multiple hypotheses, select the one that makes the fewest assumptions
parsimony
a change from an ancestral state
derived character
no nucleus, mitochondria, chloroplast, branched membrane lipids
Yes peptidoglycan
Introns are rare
Chromosomes are circular
bacteria
no nucleus, mitochondria, chloroplast, peptidoglycan
Yes branched membrane lipids
Some introns
Circular chromosomes
prokaryotic, usually found in extreme environments
archaea
Yes nucleus, mitochondria, and chloroplast
No peptidoglycan or branched membrane lipids
Introns are common
Chromosomes are linear
eukarya
sunlight powers metabolic processes
photoautotroph
inorganic chemicals serve as the energy source
chemoautotroph
consumes chemicals or other organisms
chemoheterotrophs
the transmission of DNA from parent to offspring
horizontal gene transfer
three shapes of bacteria
bacillus, coccus, spirillus
type of bacteria that perform oxygenic photosynthesis
cyanobacteria
some organelles used to be prokaryotic microbes
theory of endosymbiosis
spore-like cells that allow the cyanobacteria to exist in harsh environments
akinete
specialized cells in cyanobacteria that are used for nitrogen-fixation
heterocyst
supergroups within domain eukarya
excavata, SAR, unikonta
archaeplastida (not important)
cytoskeletal morphology, modified or vestigial mitochondria, 2+ flagella
excavata group
groups within excavata
diplomonadida, parabasala, euglenozoa, euglenida, kinetoplastida
supergroup composed of: stramenopiles, alveolates, and rhizarians
supergroup SAR
supergroup with tube shaped pseudopodia, contains amoebozoans and Opisthokonts
unikonta