bio 1

systematics

the study of diversification and relationships

taxonomy

the naming of groups of organisms

classification

assigning organisms to hierarchical groups

taxon

(pl. taxa) a named group of organisms

phylogeny

evolutionary history

linnaean classification from largest to smallest

domain, kingdom, phylum, class. order family, genus, species

how do you correctly write names of taxa

if typed = italics

if written = underlined

frst word capitalized, second lowercase

clade

a lineage of ALL organisms descended from a common ancestor ex= mammals

grade

a group of organisms that share similarities but not because of a common ancestor or it excludes some descendants. ex= marine vertebrates

monophyletic

a lineage with a single common ancestor ex = mammals

paraphyletic

a lineage including some but not all descendants of a common ancestor; NOT A CLADE ex = reptiles (excluding birds); a common ancestor but not all of its descendants

polyphyletic

a lineage or trait that is found in independent lineages; NOT A CLADE; ex = flying animals (birds, bats, insects)

sister taxa

groups that share an immediate common ancestor and diverged from that ancestor at the same time

branch points

the representation on a phylogenetic tree of the divergence of two or more taxa from a common ancestor

rooted trees

the common lineage from which all the species on the tree are derived is indicated at the base of the tree

convergent evolution

the independent evolution of similar features in different lineages or analogous traits

divergent evolution

evolution of one or more closely related species into different species; resulting from adaptations to different environmental conditions or homologous traits; ex = Darwin's finches

apomorphic

derived characteristic

plesiomorphic

ancestral characteristic

synapomorphic

shared derived "characteristics"

symplesiomorphic

shared ancestral characteristic

autapomorphic

an unshared, derived characteristic

features of a prokaryotic organism

no nucleus, no membrane bound organelles, no mitochondria, no chloroplasts, no cytoskeleton,

do prokaryotes form a clade? why?

no, because they share the ancestral characteristic of lacking a nucleus

why are viruses not considered to be alive?

because they cannot live without a host

prokaryotic domains

Bacteria and Archaea

explain the relationship between archaea, bacteria, and eukarya

eukarya and archaea are more closely related than bacteria.

coccus

spherical shaped cell

bacillus

rod like cell

spirillum

spiral

gram positive

purple = bacteria = peptidoglycan

gram negative

pink = archaea = psuedopeptidoglycan

fimbrae

hair like protein structures that are used to attach

pili

used to transfer plasmids during conjugation of horizontal gene transfer

endospores

way of resistance for bacteria; shell like structure

capsules

gluey outside layer that acts as a shell or a mask

why are flagella in prokaryotes and eukaryotes analogous?

they work differently and did not come from a shared common ancestor; and derived differently

horizontal gene transfer

genetic info passed from on cell to another

transformation

plasmids from environment

conjugation

plasmids passed via pili

transduction

virus mediated gene transfer

positive taxis

movement towards a stimulus

negative taxis

movement away from a stimulus

prokaryotes have more metabolic diversity. why?

they can feed by being heterotroph, autotroph, photoheterotrophs, photoautotrophs, chemoautotrophs, mixotrophs

pathenogenic

most famous for bacteria; causing harm

free living

dont have a permanent association with a host

mutualistic

2 organisms where both benefit from the association

decomposers

breakdown dead biomass

biofilms

communities of organisms that grow together

based on endosymbiont theory, where did mitochondria and cholorplasts come from?

mitochondria = alphaproteobacteria

chloroplasts = cyanobacteria

major groups of archaea

Eukarychaeota

Crenarchaeota

Korarchaeota

Nanoarchaeota

major groups of bacteria

proteobacteria, chlamydias, spirochetes, cyanobacteria, gram positive bacteria

synapomorphies shared by eukaryotes?

cells with nuclei, membrane bound organelles, sexual life cycles, linear chromosomes, mitochondria

is zygotic meiosis haploid or diploid dominant

haploid

is gametic meiosis haploid or diploid dominant

diploid

how is photosynthesis within eukaryotes polyphyletic?

through multiple endosymbiosis events throughout lineage but they all happened separately

Horseshoe crabs (Phylum Arthropoda, Class Xiphosura) have exhibited very little morphological change over 450 million years of evolution and are considered "living fossils". This is an example of ___.

Bradytely

t or f: prokaryotes are a valid taxon

false

Bacteria and archaea don't have nuclei or other membrane-bound organelles. This character state is:

Symplesiomorphic

Relative to Archaea and Bacteria, having membrane-bound organelles is a(n) for Eukarya

autapomorphy

Protists are:

paraphyletic

Which of the following phyla has NO photosynthetic members?

Apicomplexa