Biology: ECHS Evolution and Diversity

most fossils are found in what type of rock

sedimentary

relative dating

lower layers of sedimentary rock and fossils are older than the upper layers - chronological sequence - age unknown

radiometric dating

relies on radioactive isotopes, which decay or breakdown into stable isotopes at a steady rate - uses the change in isotope to calculate the age

what is the purpose of index fossils

they are used to establish and compare the relative ages of rock layers and the fossils they contain - fossil record shows that most organisms and the fossils they contains are now extinct

half life

the time require for half of the radioactive atoms in a sample to decay - after one half life, half of the original radioactive atoms have decayed - different radioactive isotopes decay at different rates, so they have different features

what is the cambrain explosion

the time period where a huge increase in diversity occured

list the major divisions of geologic time scale smallest to largest

period, era, eon

how many mass extinctions have occures

5; ordovician, devonian, permian, triassic, cretaceous

who are miller adn urey

scientists who simulated life’s origin who suggested the simple compunds found on earth could combine to form organic compounds needed for life such as amino acids

early earth gases include

carbon dioxide, water vapors, and nitrogen

microspheres

large organic molecules formed bubbles that had many characterisitics of living cells

what came first

dna then rna then proteins because rna can grow and duplicate themselves. it is simplier than dna which suggests it came first

what were the effects or early organisms on earth enviornment

the first photosynthetic organisms caused earth to cool as they converted carbon dioxide to oxygen then oxygen accumulated and the ozone formed making the sky blue

endosymbiotic theory

eukaryotic cells formed by prokaryotic cells by engulfing otther prokaryotic cells then the internal cell bgins to work like an organelle

what is the evidence behind endosymbiotic theory

mitochondria and chloroplasts with dna, m and c have ribosomes similar to bacteria, and reproduce by binary fission like bacteria

what is taxonomy

the science of naming and classifying organisms

what is binomial nomenclature

formal 2 part naming system of naming species of living organisms

what two groups of taxa make up the scientific name

the genus - the group that includes number of closely related species, and the species - populations of organisms that can potentially interbreed under natural conditions

what are the rules of taxonomy

genus is first, name is italicized or underlines, first letter of genus name is capitalized, first letter of species name is not capitalized, and the specie name is never used alone

what is a dichotomous key

a set of paired statements that can identify organisms, classifying organisms using dichotomous keys

what is the 8 taxa brodest to specific

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

what can i use to remeber taxa

donkey kong pays clubs, only for gental spankings

identify human classification

eukarya, animara (animal), chordata, mammalia (mammals), primate, hominidae, homo, sapien

what is the difference between modern classification and traditional classification

traditional used simply similarities and differiences in characteristics but is not always the same language where as modern classification applies darwin’s ideas about evolutionary relationships using a universal language

what are the 3 domains

bacteria - unicellular, prkaryotic, ecologically diverse

archaea - unicellular, prokaryotic, live in extreme environments

eukarya - eukaryotic, has a nucleus, protists, fungi, animals

what are the 6 kingdoms of life

plantae, animilia, fungi, protista, eubacteria, archarbacteria

how are organisms placed in the correct catigory

based on anatomy aka anatomical similarites and differences, and they are also based on molecular biology similarities and differences

what are cladograms

phylogenetic trees that show evolutionarhy history of derived characteristics traits not just visible similarities - shows relation

clade

a single common ancestor and all groups that have decended from that ancestor

node

a point at which 2 groups branched off from each other. it also represents the last point at which those 2 groups shared a common ancestor

derived character

a trait shared by all members of clade and only by members of the clade

what was charles darwin’s and alfred wallace’s contribution to science

the theory of evolution explaining how organisms evolved over long periods of time through descent from common ancestors in which the world is constantly changing

what are the three patterns of biodiversity

species vary globally, species vary overtime, and species vary locally

what did Hutton and Lyell determine

both that earth is extremely old and that the process that changed the earth in the past are the same process that operate in the present

what did lamarck contribute

the theory of use and disuse stating that organisms change traits during their lifetimes by selectively using or not using various parts of their bodies

what is the evidence of evolution

continental drift, biogeography, progressive fossils, anatomy, embryo development, and dna evidence

homologous structures

inherited from a common ancestor - similar structures with different functions

analogous structures

similar function but not structure

vestigial structures

inheritied from ancestors but have lost much or all of their original function

what is life’s common genetic code

the similarity in genetic code is powerful evidence that all organisms evolved from common ancestors

what are snp’s

single nucleotide polymorphism aka places where indifferent people the genetic squence varies by single nucleotide letters A, T, G, and C

what are the two sources of SNP’s

mutations - random changes in genetic code

indels - mutations cause by inseration/deletion

explain the relative theory of frequency of an allele

the number of times a particular allele occurs in a gene pool, compared with the number of times other allels for the same gene occur

single gene traits

changes in allele frequencies and thus phenotype frquency

poly genic traits

can affect the fitness of phenotypes and produce one of three types of selection including directional, stablizing, and oen that favors both extremes

directional

phenotype favors one extreme

stabilizing

favor average or norm

what is gene flow

the flow of allels in and out of a population resulting from the migration of individulas or gametes

what is genetic drift

a series of chances occurences can cause an allel to become more or less common ina population

what is the bottlenose effect

chance events of a catastrope can reduce the genetic variation within a population as long as a large portion of a population is reduced only remaining individuals can reproduce and pass their alleles on

what is the founder effect

a small portion of the population leaves to start a new population in a new location bringing only their alleles with them