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Biology
17.4 - 18
Question | Answer |
---|---|
Large scale evolutionary changes that take place over long periods of time | macroevolution |
Patterns of Macroevolution | 1Mass extinctions 2Adaptive Radiation 3Convergent evolution 4Coevolution 5Punctuated equilibrium 6Changes in developmental genes |
Possible causes of mass extinction? | Huge asteroid caused the cretaceous extinction, large volcanoes, continents changing position, sea levels changing |
What effects have mass extinction had on the history of life? | habitats/niches open, new world of geological oppurtunity, burst of evolution that produced an abundance of new species |
Process of single species or a small group of species evolving into several dif forms that live in dif ways | adaptive radiation |
What led to adaptive radiation of mammals? | disappearance of dinosaurs |
Process by which unrelated organisms come to resemble one another | convergent evolution |
Ex. of convergent evolution | sharks fin and dolphins limb |
Process by which 2 species evolve in response to changes in each other over time | coevolution |
How have plants and plant eating insects coevolved? | A number of plants have evolved poisonous compounds that prevent insects from feeding on them. Once plants begin to produce poison, natural selection in herbivorous insects began to favor any variants that could alter, inactivate, or eliminate those poiso |
Idea that evolution occurs at a slow, steady rate | gradualism |
What are some reasons rapid evolution may occur after long peridos of equlibrium? | Small population becomes isolated from main part of population, small group of organisms migrates to new environment, to fill available niches |
Patter of long, stable periods interrupted by brief periods of more rapid change | punctuated equilibrium |
T/F Evolution has often proceeded at different rates for different organisms | true |
How can hox genes help reveal how evolution occurred? | Homologous hox genes establish body plans in animals as different as insects and humans. Major evolutionary changes may be based on hox genes. |
Why do biologists use a classifications system to study the diversity of life? | to group in a logical manner |
Science of classifying organisms and assigning them universally accepted names | taxonomy |
T/F In a good system of classification, organisms places into a particular group are less similar to each other than they are to organisms in other groups. | false |
Why is it confusing to refer to organisms by common names? | common names vary among languages and even among regions within a single country |
T/F Early efforts of naming organims: Usually english | false |
T/F Early efforts of naming organisms: Often described detailed physical characteristics of a species | true |
T/F Early efforts of naming organisms: could be very long | true |
T/F Early efforts of naming organisms: It was difficult to standardize the names | true |
2-word naming system developed by Linnaeus | binomial nomenclature |
T/F Binomial nomenclature is no longer in use today | false |
T/F Each species is assigned a 2 part scientific name | true |
T/F Scientific names are always in italics | true |
T/F 2nd part of the scientific name is capitalized | false |
Genus of Ursus arctos? | Ursus |
Group or level of organization in taxonomy is called a taxonomic category or _______ | taxon |
Largest taxonomic category, smallest | kingdom, species |
2 kingdoms Linnaeus named? | Animalia and Plantae |
Taxonomic categories | kingdom, phylum, class, order, family , genus, species |
What traits did Linnaeus consider when classifying organism? | structures of dif organisms and details of anatomy |
Probles faced by taxonomists who rely on body structure comparisons? | Organisms that are quite dif from eachother evolve similar body structures |
T/F Darwins thoery of evolution changed the way biologists thought about classification | true |
How do biologists now group organisms into categories? | Biologists now group organisms into categories that represent lines of evolutionary descent, not just physical similarities |
T/F Genera place withing a family should be less closely related to one another than to memebers of any other family | false |
Strategy of grouping organisms together based on their evolutionary history | evolutionary classification |
Cladistic analysis | Considers only traits that are evolutionary innovations and is a method of evolutionary classification |
Characteristics that appear in recent parts of lineage, but not in older members | derived characters |
diagram that shows evolutionary relationships among a group of organisms | cladogram |
T/F Derived characters are used to construct a cladogram | true |
T/F some organsisms do not have RNA or DNA | false |
How do similarities in genes show that humans and yeast shar a common ancestry? | Humans have a gene that codes for myosin, a protein found in our muscles. A gene in yeast codes for a myosin protein |
A model that uses DNA comparisons to estimate the length of time that 2 species have been evolving independently | molecular clock |
Molecular clock relies on the repeating proccess of >..... | mutation |
Why are only neutral mutations useful for molecular clocks? | Neutral mutations accumulate in the DNA of dif species at about the same rate. This can reveal how dissimilar genes are. This is an indication of how long ago the 2 species shared a common ancestor |
T/F Degree of dissimilarity in DNA sequences is an indiciation of how long ago two species shared a common ancestor. | true |
Why are there many molecular clocks in a genome insteat of just one? | some genes accumulate mutations faster than some others |
T/F Scientific view of life = more complex in Linnaeus' time | false |
What fundamental traits did Linnaeus use to separate plants from animals? | animals = mobile, use food for energy, plants = gree, photosynthetic organisms that used energy from the sun |
What type of organisms were later place in the kingdom Protista? | microorganisms |
Mushrooms, yeast and molds have been place in their own kingdom... | fungi |
Why did scientists place bacteria in their own kingdom, the Monera? | scientists realized tha bacteria lack nuclei, mitochondria, and chloroplast found in other forms of life |
2 groups into which monera have been separated? | eubacteria, archaebacteria |
6 kingdoms | animalia, eubacteria, protista, fungi, plantae, archaebacteria |
More inclusive category than any other including the kingdom | domain |
What type of analyses have scientists used to group modern organisms into domains | molecular |
3 domains | bacteria, archaea, eukarya |
Bacteria | prokaryotes, rigid cell walls that contain peptifdoglycans |
T/'F All members of the domain bacteria are parasites | false |
Archae | unicellular |
T/F Many members of the domain archaea can survive only int he absence of oxygen | true |
Eukarya | have nucleus |
Protista | slime molds and giant kelp |
fungi | cell walls of chitin |
plantae | mosses and ferns |
animalia | no cell wall, chloroplasts |