BSCI EXAM 2 REVIEW UNIT PLANT DIVERSITY Lecture 8 Plant Systematic and Darwinism Evolution Plant Systematics Common Names evolved over centuries in many different languages problem diff name diff region Scientific Names Kingdom Division Class Order Family Genus Species First name genus second name species ex Humans homo genus sapiens species Taxonomic hierarchy species with similar characteristics are grouped in a genus which are then group into families Living organisms are now classified into 3 domains archaea eubacteria eukaryota and 6 KINGDOMS Archaebacteria Eubacteria Protista Planae Fungi Animalia Plants further classify into 10 divisions 1 Broyphyta mosses liverworts 2 Psyolophyta 3 Lycophyta club mosses 4 Sphenophyta horsetails 5 Pterophyta ferns 6 Cycadophyta cyads 7 Ginkiphyta ginko biloba 8 Coniferophyta conifers 9 Genophyta gnetophytes 10 Magnoliophyta flowering plants What is a Species A set of Individuals that are closely related by decent from a common ancestor and ordinarily can reproduce with each other but not with members of any other species Morophological species concept based on their morphological features shape size body parts Biological species concept group of interbreeding populations Offspring are fertile Evolutionary species concept group of individuals with a common evolutionary lineage Carolus Linnaeus Binomial System of Nomenclature genus and species names are used classified plants by flowers EVOLUTION a genetic change in population of organisms that occurs over time often adapting to an environment or way of life Changes must be genetically inherited not acquired Lamark Pre Darwinian Lamarckism holds that traits acquired during lifetime of an organism can be passed to its offspring Based his theory on Use it or lose it and inheritance of acquired traits disproved Darwin On the Origin of Species by Means of Natural Selection Natural selection differential survival and reproduction of individuals inherit the advantageous traits 4 premises o Variation members of pop have individual differences that are inheritable Key is sexual reproduction o Over production natural populations reproduce geometrically Producing much more offspring that will survive o o Competition Individuals compete for limited resources struggle for existence Survival to reproduce only those that are better suited in environment survive and reproduce Survival of the fittest Evolution descent with modifications over time new species are created Artificial selection selective breeding practice by humans on domestic animals and plants Rates of Evolution two interpretations about speed of evolution based on fossil records o Gradualism traditional view occurs as a slow and steady accumulation of changes in organism o Punctuated Equilibrium evolution proceeds with periods of inactivity followed by rapid evolution Supported by fossil records Long periods of stasis no change in species Followed by rapid change However fossil evidence is only evidence of morphology while evolution encompasses ecology biochemistry and behavioral changes 1 Lecture 9 Evidence for evolution and plant adaptations Three types of Natural Selection 1 Directional selection one trait at the extreme of the range is favored over individuals with the average or opposite extreme of the trait Stabilizing selection the average trait is favored over the extreme trait 2 3 Disruptive selection the extreme traits are favored over individuals with the average traits Evidence in support of evolution found in extant organisms living 1 Comparative anatomy a Homologous organs similar in form in different organisms due to a common evolutionary origin i Share same common origin but may have different functions ii Ex bone structure found in human arm bat wing dolphin flipper b Analogous organs similar in look or function in different organisms but not share evolutionary origin i Ex wings of insects vs wings of birds ii iii Convergent evolution unrelated organisms in a similar env evolve similar adaptive structures c Vestical organs non functional and degenerative an organ loses its function no selective advantage to In plants similar function of tendrils but diff origin leaf vs stem have it but also no selective advantage to get rid of it i Leg bones in snakes whales wisdom teeth appendix 2 Mimicry and protective coloration a Mimicry harmless species may resemble dangerous species b Protective coloration allows an organism to blend with environment i Stone plants protect against herbivores 3 Developmental biology 4 Biogeography a Early embryos of different mammal species look very much a like share common features a Unequal distribution of organisms on earth i Kangaroos in Australia b Endemic species occur online in a particular area and are usually rare 5 DNA biochemistry molecular biology a Genes provide an evolutionary record b Evolved from ancestor same DNA Fossils evidence for evolution from extinct organisms Fossil records most compelling evidence for evolution Adaptations process by which genetic changes occur Traits anatomical physiological or biochemical that promote the survival and reproductive success of an organism in a particular environment as a response to environmental pressures Adaptation may originate as mutations examples of plant adaptations Morphological Leaves can adapt to many different functions Co evolution the long term evolutionary adjustment of one group of organisms to another reciprocal process Symbiosis Protection plants try to avoid predation Coloration different flowers colors attract different pollinators Parasitism Communalism 0 o o o Mutualism o Plant Microorganism symbiosis Nitrogen fixing bacteria and legume plant bacteria receives sugar plant receives nitrogen for nutrient fungus receives sugars food and plant receives phosphate and water o Pollination coevolution of plants and insects Lecture 10 Viruses Prokaryotes Bacteria Eukaryotes Fungi 2 Viruses non living organisms Have protein coat for protection and nucleic acid DNA for information on how to copy cannot replicate on its own needs a host intercellular parasite o Uses cell machinery of host to replicate to produce more viruses diff shapes varieties virons Cause diseases ex herpes hepatitis rabies ebola influenza vaccine helps protect outbreaks antibiotics wont work Human viruses HIV HPV sexual transmission Norovirus stomach flu Plant viruses tobacco mosaic virus rose mosaic virus spots on fruit wheat stunt virus Living organisms are