Unit 10: Taxonomy and Evolutionary Patterns

serial endosymbiosis theory

serial endosymbiosis theory

it explains the orgins of nucleated eukaryotic cells by the merging of archaebacterial and eubacterial cells

geologic time scale

divides up the history of the earth based on organisms that existed duirng that time

precambrian time

• earliest eon

• precedes the cambrian perion and phanerozoic eon

• the age of early life

  • jellyfush, soft-bodied creautures, worms

  • mostly uninhabited land

cambrian explosion

• approx. 530 million years ago

• a wide variety of animals emerged onto the evolutionary scene

• most of the major animal groups started to appear

Paleozoic era

• 541 - 252 million years ago

• diversification of fish and abundance of marine animals (trilobites, molluscs, small shelled organisms)

• formation of many land forms we know of today (eg. Appalachian Mountains, creation of Pangaea)

• contains the Permian, Carboniferous, Devonian, Silurian, Ordovician, and Cambrian periods

mesozoic era

• 251.9 - 60 million years ago

• age of reptiles (dinos, crocodiles, pterosaurs)

• Pangea begins to separate into the modern continents + formation of the Rocky Mountains

• contains the Triassic, Jurassic, and Cretaceous periods

cretaceous

• 145 - 66 million years ago

• last portion of the age of dinos/mesozoic era

• by then end of this era, the continents look very similar to how they are today

• defined by a layer of chalk formed in western Europe

• first flowering trees

• ends with a mass extinction (K-T or K-pg) resulting in 70% of the species being extincy

cenozoic era

• 66 - 0 million years ago

• recent life

• the age of mammals (humans and many others)

• split into many epochs (Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene)

mass extinction

clears the way for surviving organisms to evolve

fossil record

a collection of all the fossils found on earth, documenting the history of life on our planet

extinct/extant

extinct: no longer in existence, died out

extant: still existing, not destroyed or lost

three-domain system

a classification system that groups all cellular life into 3 domains - Archaea, Bacteria, and Eukarya

five-kingdom system

A classification based on things like mode of nutrition, thallus organization, cell structure, phylogenetic relationships, and reproduction.

• Consists of Monera (unicellular prokaryotic organisms), Protista (protists), Plantae (plants), Fungi, and Animalia (animals)

archaea

• prokaryotic (no cell membrane)

• oldest species of organisms

bacteria (eubacteria)

• prokaryotic (no cell membrane)

• membrane posseses discyl glycerol diester lipids

• single celled

plantae (plants)

• all plants (living or extinct)

• highest taxonomic group organisms can be grouped into

protista (protists)

a kingdom consisting of singled celled (mostly) organisims that are neither plants nor animals nor fungi

animalia (animals)

• the kingdom consisting of all the animals (including humans)

analogous structures

features that are similar in function but not necessarily in structure, do not derive from a common ancestor

divergent evolution

one common ancestor species evolves into many diverse forms

convergent evolution

organisms that are different from one another develop similarities because they live in the same type of environment

amino acid sequencing

the process of identifying the arrangement of amino acids in proteins and peptides

Carolus Linnaeus

• a Swedish biologist and physician

• created a system of naming plants and animals, the binomial system

phylogeny

the representation of the evolutionary history and relationships between groups of organisms

phylogenetic tree

a diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor

binomial nomenclature

• the formal naming system for living things

• must be written in italics, has 2 parts, genus (larger family) is written first and must be capitalized, the specific epithet (specific name) is never capitalized and must go second

taxon/taxonomy

the science of naming, describing, and classifying organisms

cladogram

diagrams that depict the relationships between different groups of taxa called clades

taxonomic ranks

the relative level of a group of organisms (taxon) in an ancestoral hierarchy

• consists of species, genus, family, order, class, phylum, kingdom, and domain