Plant Science Exam 2 Study Guide: 3/20/13Lecture 8: 1) Plant Systematics- branch of botany concerned with the naming, identification, evolution, and classification of plants2) Plant Taxonomy- science of naming and classifying plants 3) Genus or (genera)- a formed group of similar plant speciesa) Genera are grouped into familiesb) Then into orders, classes, divisions and kingdomsc) Kingdom division  class  order  family  genus  speciesd) “King David came over for great sex”4) Species name- each species has a single correct scientific name in Latin called binomial (two names)- ALWAYS italicized or underlineda) First name= GENUS nameb) Second name= SPECIES namei) EX: human- homo sapiens, cat- felis catus, dog- canis, familiaris5) Living organisms are classified into 3 domains, 6 kingdoms, 10 Divisionsa) 3 DOMAINSi) Archaeaii) Eubacteriaiii) Eukaryotab) 6 KINGDOMSi) Archaebacteriaii) Eubacteria (true bacteria)iii) Protistaiv) Plantaev) Fungi vi) Animaliac) 10 DIVISIONSi) Bryophyta – mosses, liverwortsii) Psylophytaiii) Lycophyta – club mossesiv) Sphenophyta – horsetailsv) Pterophyta – fernsvi) Cycadophyta – cycadsvii)Ginkgophyta – Ginkgo bilobaviii) Coniferophyta – conifersix) Gnetophyta – gnetophytesx) Magnoliophyta – flowering plants6) Species- set of individuals that are closely related by descent from a common ancestor and ordinariy can reporduce with each other but NOT with members of any other speciesa) ** Some plants look the same but due to poluploidy (more than the diploid number of chromosomes) they cannot interbreed EX: ferns, evening primrose7) Morphological speices concept- based on their morphological features (SHAPTE, SIZE, BODY PARTS)8) Biological species concept- group of interbreeding populations. Offspring are fertilea) Species are groups of actualy or potentially interbreeding natural populations which are reproductively isolated from other such groups9) Evoltionary species concept- group of individuals with common evolutionary lineage10)** Broccoli, kale, cabbage, califlower are all members of SAME SPECIES 11)Carolus Lunnaeus- swedish scientist (doctor and botanist) “father of systematic botany”, and “father of taxonomy”a) Established modern system of nomenclature- his BINOMIAL system of nomenclature was where genus and species names were usedb) Compared flowered to human sexuality 12)Evolution- a genetic change in a population of organisms that occurs over time, often adapting to an encironment or way of lifea) Evolutionary changes must be GENETICALLY INHERITED, not acquired13)Creationism- main belief that all organisms were specially created, unchangingEvolutionary thinking…14)Aristotle (350 BC) – saw design and purpose in nature, living organisms went from imperfect to perfect, complex state15)George Cuvier (1790’s) – Proposed ‘Catastrophism’, with creations and extinctions causedby floods and droughts16)James Hutton – geologist who championed “Gradualism”, convinced that Earth was millions of years old 17)Jean-Baptiste Lamarck (1744-1829) – French naturalist, proposed a theory that organisms were driven by some inner force toward greater complexity. But thought that org. could pass on traits to their offspring that they acquired during their lives “Lamarckism”a) Lamarckism- traits acquired or dimished during the life of an organism can be passed to its offspring. Theory is based on two observations…i) 1. “Use it or lose it”-ii) 2. Inheritance of acquired traits from ancestorsb) EXAMPLES: stretching by giraffes to reach elaves leads to offspring with longer necks; strengthening of muscles in a blacksmiths arm leads to sons with like muscular development… THEORY WAS DISPROVED!18)Charles Darwin (1809- 1882)- observed island animals are similar to mainland animal species but show differences due to island conditionsa) * Human populations are controlled by environmental factors (war, famine, diseases)b) He thought or organisms not as constant, unchanging or “specially created beings” c) Concept of NATURAL SELECTION developedd) Natural selection- the differential survival and reproduction of individuals with inhertiable characterists- nature is the selective mechanismi) Evolution- descent with modification19)Microevolution- change of allele frequencies in a population over a short period of time a) Natural selectioni) Works on the individual phenotype  which in turn changes the populations gene poolii) Long periods of time must be available in order to change to a completely difference species, because change is slowiii) Those that don’t inherit the favorable genes are not likely to survive/ reproduce iv) Gradually the species evolve as more individuals carry the favorable traitsb) Natural Selection 4 premises i) Variation – Members of a population have individual differences that must be inheritable; WONT work in a population of CLONES, because SEXUAL REPRODUCTION is the key to variationii) Overproduction– Natural populations reproduce geometrically, producting more offspring than will survive; Thomas Malthus said thisiii) Competition – Individuals compete for the same limited natural resources; “struggle for existence”iv) Survival to reproduce – Only those individuals that are better suited to the environment survive and reproduce; “survival of the fittest” c) Mutationsd) Gene flowe) Genetic driftf) Non- random mating20)Artificial Selection- selective breeding as practiced by humans on domesticated plants and animalsa) Ex- teosinte vs. modern corn21)Macroevolution- evolution that results in the formation of new species or other groupings of living things22)Rates of evolution- two interpretations about the speed of evolution based on FOSSIL recorda) Gradualism (Traditional view)- states that evolution ovvurs as a slow and steady accumualtion of changes in organism (darwinian evolution) not much evidenceb) Punctuated equalibrium- evolution proceeds with periods of inactivity, followed by periods of very rapid evolutio; conditions remain CONSTANT for long periods of timei) Fossil records support this viewii) Long periods of no change in species and then rapid changeiii) There may be stasis in morphology while there is still active evolutionary changes happeningLecture 9:1) 3 Types of Natural Selectiona) Directional Selection- one trait at the extreme of the range is favored over individuals with the average or opposite extreme of the traitb) Stabilizing