Final study guide

Final Exam Study Guide Know these people Carl Linnaeus- Swedish botanist who established a system for naming species that is still in use today; two-part name unique to each type of organism Jean Baptists Lamarckian-proposed that individuals change in response to challenges posed by the environment and the changed traits are then passed on to offspring Charles Darwin- said that species change over time but do not progress; individual variation is important and variation is what drives evolution Biodiversity How many species have been described? Approximately 1. 5 million (114 of all species) How many species remain to be described? What animals account for the greatest amount of species diversity? Insects How do we estimate biodiversity? Genetic diversity, species diversity, ecosystem diversity, change through time -variety and variability of life on earth, measured by species What are ecosystem services? Processes that increase the quality of the biotic environment -atmosphere and c limate, freshwater, nutrient cycling, pollination, pest population, disease What is an ecological footprint?How many additional planet earths would be required if all humans had the ecological footprint of an American? 4 planets Why is biodiversity important? Why study biodiversity? Economical and biological benefits Science What is a theory and how does it differ from a hypothesis? Well a hypothesis is a possible or tentative explanation for scientific findings that a scientist discovered during research. A theory is a tested by other scientists who get the same results as the previous scientists hypothesis Evolution and Natural Selection Why did Darwin delay the publication of The Origin of Species?Because of â€Å"special creation† was still very popular What is unfamiliarity's and how does it relate to the process of Natural Selection? Their ideas both relied on low changes over time rather than cataclysmic events that caused sudden upheaval or change What is a geometric progression;- -is a sequence of numbers where each term after the first is found by multiplying the previous one by a fixed, non-zero number called the common ratio -population growth what is an arithmetic progression? -increases by a constant difference (e. . , units of 1 or 2 or 3) -food supply -supply gradually increases with large population jumps How do these relate to populations and natural selection? – lack of resources causes competition Review the medium ground finch study (Gasping forties). What type of selection? Directional selection What influenced beak size? Since only big seeds became available, individuals with particularly large and deep beaks were more likely to crack these fruits efficiently enough to survive How did this relate to rainfall? He drought cause the sources of seeds as food to decline What are the conditions necessary for Natural Selection? – individuals vary -some variations are heritable -more offspring are produced than can survive - individuals with traits that confer an advantage are more likely to survive and reproduce What are the agents of evolutionary change – review notes on tuition, coneflower, nonrandom mating, genetic drift.Mutation-constantly introduces new alleles at all loci -increases genetic diversity in population -ultimate source of all genetic variability -random with respect to fitness Gene Flow- the movement of alleles from one population to another -random with respect to fitness -tends equalize allele frequencies among populations Nonrandom matting- nonrandom mating between relatives -causes inbreeding depression -helps selection weed out deleterious alleles Genetic Drift- any change in the allele frequencies in a population that is due o chance (luck, sampling error) ;causes allele frequencies to drift up and down randomly over time What is fitness? The ability of an individual to survive and reproduce, relative to other individuals in that population What is artificial selection? S elective breeding of domesticated plants and animals to produce offspring with desired genetic traits How does natural selection produce major change? Trial selection is the tendency of the ones best suited to survive in their environment to survive longer and pass on their genes more often – those genes then become more common and the harmful rations die out, gradually reshaping all life and fine-tuning it to it's environment. What is homology? The occurrence of similar features in different species because they both inherited the trait from a common ancestor What is the most common cause Of homophony? -convergent evolution -occurs when natural selection favors similar solutions to problems posed by a similar way of life What is a vestigial structure? Any rudimentary structure of unknown or minimal function that is homologous to functioning structures in other species -are thought to reflect evolutionary history How do imperfect structures relate to the theory of evolution b y Natural Selection?If evolution is true, then â€Å"imperfect design† is expected, because natural selection works to make an organism well-adapted, but not perfectly adapted, to their environment What is convergent evolution? Review the fish ichthyology example from class and the text. Process by which unrelated organisms independently evolve similarities when adapting to similar environments. Starting about 200 million years ago, these marine reptiles evolved body plans (and behavioral patterns) strikingly similar to those of odder dolphins and bluffing tuna (great example of convergent evolution) Be able to recognize disruptive, directional, stabilizing selection.Disruptive both extremes are favored, and the average phenotype is selected against – relatively rare -maintains genetic variation -plays a role in speciation-the generation of new species Directional- one extreme is favored, and the average phenotype (and the other extreme) is selected against -changes th e average value of a trait Stabilizing- reduces genetic variation -the average phenotype is favored, and both extremes are selected against – he average value of the trait does not change over time What is the difference between macroeconomics- Large-scale evolution occurring over geologic time that results in the formation of new taxonomic groups. ND microinstruction – evolution resulting from small specific genetic changes that can lead to a new subspecies Hardy-Weinberg You will not be asked to do any Hardy-Weinberg calculations What is the basic tenet of the Hardy-Weinberg Theorem? When alleles are transmitted via meiosis and random combination of gametes, their frequencies do not change over time -for evolution to occur, some other actor or factors must come into play -if the frequencies of alleles AH and AH in a population are given by p and q, then the frequencies of genotypes AH AH , AH AH, and AAA will be given by pa, ops, and sq for generation after generatio n What are the assumptions of the H-W Theorem? O natural selection -no genetic drift (no random allele frequency changes) -no gene flow via immigration or emigration -no mutation -random mating (with respect to the gene in question) pa -the predicted frequency of the offspring AH AH genotype* ops-the predicted frequency of the offspring AI genotype + sq -the predicted regency of the offspring AAA genotype= 1 : what are the allele frequencies, what are the genotype frequencies in a non-evolving population? Frequency of dominant allele the frequency of the recessive allele frequency of AAA (homozygous dominant) ops= frequency of AAA (heterozygous) sq= frequency of AAA (homozygous recessive) How do you recognize a population not in H-W equilibrium? If it does not equal one Why would a population not be in H-W equilibrium? B/c changes would occur and that would not be realistic Species and speciation Review the Biological Species Concept. Cost widely accepted concept -defines species as a population or group whose members have the potential to interbreed with one another in nature to produce viable, fertile offspring Be able to differentiate between Predating/Precocity-individuals of different species are prevented from mating, Postdating/Precocity and Posthypnotic- when individuals from different populations do mate, but species will have low fitness or fitness or offspring will be sterile barriers. What are the predating-Factors which cause species to mate with their own kind (assertive mating) and postdating barriers-Genomic incompatibility, hybrid amiability or sterility What are posthypnotic barriers? What is a hybrid?Temporal isolation-populations are isolated because they breed at different times Habitat Isolation- populations are isolated because they breed in different habitats Behavioral Isolation- populations do not interbreed because their courtship displays differ Gametes Barrier- mating fail because eggs and sperm are incompatible Mechanical Isolatio n- mating fail because male and female reproductive structures are incompatible Hybrid Viability- hybrid offspring do not develop normally and die as embryos Hybrid Sterility- hybrid offspring mature but are sterile as adults Hybrid-the offspring of parents from two different strains, populations, or species In very general terms what does the Biological Species Concept state about the nature of species? What are some of the problems with the Biological Species Concept? Tot applicable to asexual or fossil species; difficult to assess if populations do not overlap geographically Be able to define the terms symmetric-occurs even though gene flow is possible; is rare or nonexistent – even though symmetric populations are not physically isolated, they may be isolated by preferences for different habitats and allophonic- begins with physical isolation via either dispersal or vicariate What is the phylogeny species concept? -based on reconstructing the evolutionary history of popul ations What is the morphological species concept? Identifies evolutionary independent lineages by differences in morphological features – based on the idea that distinguishing features are most likely to arise if populations are independent and isolated from gene flow The Fossil Record and Mass extinctions What are the different types of facsimiled materials?Thousandth Microfossils- first animals on Earth -include tiny sponges Dedicated faunas- -include sponges, jellyfish, and comb jellies as well as facsimiled burrows, tracks, and other traces from unidentified animals -small, have no shells, limbs, heads, mouths, or feeding appendages -sat immobile on the seafloor, or floated in the Water Burgess Shale Faunas- sponges, jellyfish, and comb jellies, arthropods, and mollusks -tremendous increase in the size and morphological complexity of animals occurred, accompanied by diversification in how they made a living Fossil Intermediate- we can see the bridge between where we start ed and here we are now with these intermediate fossils How are rocks in fossils preserved?What are fossil intermediates? What was the Cambrian Explosion? When did it occur? About 563 million years ago What is a mass extinction? How many are there in the paleontologist record? Result from extraordinary, sudden, and temporary changes in the environment , 5 records What is the sixth mass extinction? The ongoing extinction of Earth's creatures caused by humans What are some of the putative causes for the Permian mass extinction? When did it occur? What percentage of species went extinct? 0% 251 million years ago When was the KIT mass extinction? 65 million What is the evidence that points to an asteroid strike as the trigger of the KIP extinction?Sedimentary rocks that formed at the KIT boundary contain very high amounts of iridium (rare on Earth, common in meteorites) -In Haiti, shocked quartz and micrometeorites are abundant in rock layers from this time period -The huge crater off th e coast of Mexico Yucatan Peninsula Review the timing and general characterizations of the Paleozoic-saw the origin and initial diversification of the animals, land plants, and fungi, as well as the appearance of land animals, Pre-Cambrian-life was exclusively unicellular for most Of Earth's history -oxygen was virtually absent from the oceans and atmosphere for almost 2 billion years after the origin of life, Mesozoic- extinction of dinosaurs -in terrestrial environments of the Mesozoic, gymnosperms were the most important plants and dinosaurs were the most important vertebrates, Cenozoic-on land, angiosperms were the most important plants and mammals were the most important vertebrates and Cambrian Phylogeny How does the principle of parsimony apply to phylogeny reconstruction? Deer parsimony, the most likely explanation or pattern is the one that implies the least amount of change -a computer compares the branching patterns that are theoretically possible and counts the number of changes in DNA sequences required to produce each pattern Define the following terms: contemporary-a trait found in certain groups of organisms that exists in no others -homologous trait (inherited from a common ancestor), Primitive A structure which is NOT exclusively shared only by all members of a group by virtue of descent from a common ancestor -cannot be used to extinguish between members of a group because all actually or ancestrally possess the Structure -Example: Vertebrae are possessed by all birds but also by all other vertebrates.Possession of vertebrae cannot be used to distinguish the birds from other batteries since all batteries including birds share that trait, ancestral-A trait shared by all members of a group through a common ancestor. , derived-A structure which IS exclusively shared ONLY by all members of a group by virtue of descent from a common ancestor -Example: Among vertebrates, feathers are possessed by all birds ND by NO OTHER VERTEBRATE -Possession of feathers CAN be used to didst anguish the birds from other batteries since no batteries except birds share that trait.. Of the above which provide the only real evidence for relationship? Derived Trait How do you establish if a character is derived or ancestral (hint: outgrip and ingrown)- Assume that the character in the outgrip is ancestral.Fifth character is different in the ingrown, then it is considered derived -To determine whether a character is ancestral or derived compare the character in the ingrown with that of the outgrip Define: monopolistic-an evolutionary unit that includes an ancestral population and all of its descendants but no others (also called a clawed or lineage), paralytic-an evolutionary unit that includes an ancestral population and some but not all of its descendants -meaningful unit in evolution, polytechnic-composed of unrelated organisms descended from more than one ancestor. Be able to recognize the above terms within the context of a phylogeny tree. O f the above terms which one is preferred? – monopolistic group Which is most likely the reality of any group? Reparability group Prokaryote (study sections 28. And 28. 3) What feature has contributed significantly to bacterial diversity? Be able to differentiate been gram-positive- have cell walls composed of a thick layer of pedagogical -bacteria that look purple when treated with a gram strain and gram-negative-bacteria that look pink when treated with a gram stain bacteria have a cell wall composed of a thin layer of pedagogical and an outer phosphoric layer bacteria. Review bacterial metabolic diversity (heterodox-acquire carbon containing compounds from other organisms, lithograph-oxidize inorganic ions such as ammonia or methane to fuel cellular aspiration etc. What features distinguish Reach-no nuclear envelope -circular chromosome -all unicellular -flagella spin like bacterial flagella, but in a distinctive molecular composition have unique phosphoric in their plasma membranes, Bacteria-no nuclear envelope -have pedagogical in their cell walls -flagella spin like propeller -almost all unicellular and Eukaryote-nuclear envelope -flagella undulate back and forth? Are prokaryote monopolistic-yes, because there are two main lineages that diverged very early in the history of life Protests (study sections 29. 1 , 29. 2 and 29. ) What is the domain Eukaryote? What is the endometriosis origin of eukaryote – who proposed it and what is the evidence supporting it?Mitochondria are most closely related to what group of bacteria – to what group are chloroplasts most closely related? Do protests form a monopolistic group? What groups must be included? Land Plants (study sections 30. 1 and 30. 3) What group is most closely related to land plants? Green Algae What features were the main features that allowed plants to inhabit and subsequently diversify on land? Terrestrial habitats have more sunlight and more CA than aquatic habitats -Preventing water loss: cuticle and stomata -upright growth and vascular tissue Review the general features of land plant phylogeny. What were the major features to evolve over the course of land plant history?