Exam # 2 Study Guide Lectures: 7 - 12 Chapter 5 (Evolution & Gene Frequencies) 1. Define: population, gene pool, gene flow, Hardy-Weinberg equilibrium or theorem, genetic drift, founder effect, population bottleneck, mutation, selection pressure, speciation, polymorphism, balanced polymorphism, reproductive isolation, species, allopatric speciation, sympatric speciation, heterozygote superiority- Population: groups of individuals of the same species that occupy a given area at the same time and share a common set of genes- Gene pool: the sum of all alleles for all traits in a sexually reproducing population is a pool of hereditary resources for the entire population.- Gene Flow:changes in relative allelic frequency from the migration of individuals- Hardy-Weinberg Equilibrium: when all assumptions of the hardy-weinberg theorm are met and there is no evolution occuring- Genetic drift: chance events influencing the frequencies of genes in populations- Founders effect: changes in gene frequency that occur when a few individuals from a parental population colonize new habitats- Population Bottleneck: changes in gene frequency that result when numbers in a population are drastically reduced, and genetic variability is reduced as a result of the population being built up againfrom relatively few surviving individuals- Mutation: Change in allele frequency- Selection pressure: the tendency for natural selection to occur- Speciation: the process by which two or more species form from a single ancestral stock- Polymorphism: occurs when 2 or more distinct forms (phenotypes) exist in a population without a range of phenotype between them- Balanced polymorphism: occurs when different phenotypes are maintained at stable frequencies- Reproductive isolation: when individuals are prevented from mating, even though they may occupy overlapping ranges.- Species: a group of populations in which genes are actually, or potentially, exchanged through multiple generations. Numerous problems with this definition make it difficult to apply in all circumstances- Allopatric speciation: speciation that occurs in populations separated by geographical barriers- Sympatric Speciation: speciation that occurs in populations that have overlapping ranges- Heterozygote superiority:2. Carriers of the sickle-cell allele are resistant to the deadly form of ______________. - Malaria3. What are the assumptions of Hardy-Weinberg? - Population size must be large, this ensures genetic drift does not exist.- Individuals cannot migrate into or out of the population.- Mutations must not occur.- Sexual reproduction must be random. BZ 110 1st Edition4. Regarding Hardy-Weinberg equation, what are p and q? What do p and q add up to? In the equation p2 + 2 pq + q2 = 1, what does p2 , q2 and 2 pq represent? - p+q=1o p= number of dominant alleles in a populationo q= number of recessive alleles in a populationo If you are given p, be able to calculate q.- p2 + 2 pq + q2 = 1o p^2= Homozygous dominant individuals in a populationo 2pq= heterozygous individuals in a populationo q^2= homozygous recessive individuals in a population5. How are the 2 subspecies of African elephants different? Why are some scientists proposing that the animals should be considered 2 distinct species? - The two groups of elephants have little gene flow between them, therefore should be considered different species.6. List modes of selection, describe each and be familiar with examples used in class or other examples. - Directional selection: when individuals at one phenotypic extreme are at a disadvantage compared toall the other individuals in the population.- Disruptive or diversifying selection: when individuals of the most common phenotypes are at a disadvantage, creating a sub-population- Sexual selection: when individuals have varying success obtaining mates- Stabilizing selection: when both phenotypic extremes are harmful7. What are reproductive barriers? List those discussed in class. Chapter 6 (Ecology)8. Define or describe and give examples if appropriate: ecology, energy, heterotrophic, autotrophic, energy budget, gross energy intake, tolerance range, range of optimum, habitat, carrying capacity, density-dependentfactors, density-independent factors, torpor, hibernation, winter sleep, aestivation, parasitism, commensalism, mutualism, symbiosis, camouflage, cryptic coloration, warning coloration, mimicry, food chain.- Ecology: the study of relationships of organisms to their environment and to other organisms- Energy: ability to do work- Heterotrophic: animals energy supply through ingesting other organisms- Autotropic: energy through photosynthesis or other carbon-fixing activities- Energy Budget: Animals total energy intake and description of how they use and lose energy- Gross energy intake: Total energy contained in the food- Tolerance range: for any environment animals live within a certain range of values- Range of optimum: conditions where an animal is most successful- Habitat: includes all the living (Biotic) and non-living (abiotic) characteristics of an area in which an animal lives- Carrying Capacity: the maximum population size that an environment can support- Density dependent factors: more severe when the populations density is high or sometimes too low- Density independent factors: influence number of animals without regard to the number of individuals per unit space (density)- Torpor: a state of dormancy resulting from a small endotherm resulting metabolic rate and body temperature.- Hibernation: condition of mammals that involves passing the winter in a tropid state in which the body temperature drop to nearly freezing and metabolism drop close to zero. May last weejs ir months- Winter sleep: a period of inactivity in which a mammals body temperature remains near normal and the mammal is easily aroused- Aestivation:- Parasitism: when one organism is benefitted and the other organism is harmed- Commensalism: when one organism is benefitted and the other organism is neither benefitted nor harmed- Mutualism: when both organisms benefit- Symbiosis: the living together of two different species in an intimate relationship.- Camouflage: color patterns that help hide it from other animals- cryptic coloration: animal takes on color pattern in its environment to prevent the animals from being seen by other animals- warning coloration: animal advertises that its dangerous through its coloration- mimicry: when a species resembles other