Population 1 Population 2. A a A a p 1. 1-m m m 1-m. A a A a. ' p 2
|
|
- Thomasine Barnett
- 7 years ago
- Views:
Transcription
1 Gene Flow Up to now, we have dealt with local populations in which all individuals can be viewed as sharing a common system of mating. But in many species, the species is broken up into many local populations with restricted amounts of interbreeding. Therefore, the system of mating within differs from the system of mating between. The system of mating between local populations determines the amount of GENE FLOW. We will start with a simple model in which two, infinitely large local populations experience gene flow by exchanging a portion m of their populations each generation. Consider 1 locus with 2 alleles as follows: Population 1 Population 2 q 1 p 2 q 2 1-m m m 1-m ' q 1 ' p 2 ' q 2 ' With neutrality, one has that ' = (1-m) + mp 2 p 2 '= (1-m)p 2 + m '- = p1 = -m( -p 2 ) p 2 = -m(p 2 - ) These equations show that gene flow acts as an evolutionary force (ie. alters allele frequencies) if 1) m>0 (the local populations are not completely reproductively isolated) and 2) p 2 (the local populations are genetically distinct to some degree - - this will always be true if the local populations are finite in size and had much previous isolation -- this insures divergence by genetic drift). In the special case where =0 and p 2 >0, then gene flow introduces new genetic variability into the population. In this sense, gene flow acts like mutation. However, unlike mutation, gene flow can alter frequencies at many loci simultaneously and can cause radical and extremely rapid shifts in allele frequency.
2 Conditions causing m>0. Although this appears simple, m in reality represents a complex interaction between the pattern of dispersal and the mating system. For example, inbreeding (in the pedigree sense) can greatly reduce the opportunity for gene flow, even if the individuals are in physical proximity. E.g., the Tauregs (an Arabian tribe) mate almost exclusively with cousins. As a result, this tribe shows almost no gene flow with other tribes with which they are physically intermingled. Assortative mating can also greatly reduce the amount of gene flow. E.g., Western Grebes had apparently split and differentiated into two color morphs (light and dark) in the past. These two morphs now occur together in certain parts of the West. In one population, expected 33% of the mating pairs to be mixed under random mating; but due to strong positive assortative mating, only had 1.2% of pairs mixed. This greatly reduces gene flow and allows the maintenance of all the genetic differences between the color morphs, and not just the loci that determine the color. The reason is simple, although there may be linkage equilibrium within each color phase, with respect to the global population, all loci that are differentiated between the phases will show disequilibrium with the color loci. Another example of this is the European corn borer, which has two pheromone races that are now broadly sympatric. There is strong assortative mating for pheromone phenotype, and hence despite sympatry, the races have maintained much differentiation at isozyme loci that have no impact on the pheromone phenotype directly. In contrast, disassortative mating enhances m for all loci. E.g., D. melanogaster has strong disassortative mating pheromone system, and shows much less differentiation than corn borers and is effectively a single, cosmopolitan species showing little geographical differentiation (except for a handful of selected loci and inversions) on even a continental basis. It is also important to note that the assortative or disassortative mating that determines m for all loci can be based on a non-genetic phenotype. This was already noted for the Amish who have assortative mating based on religion and who, as a consequence, maintain extreme genetic distinctiveness from surrounding populations. Likewise, social castes in Chile are strong determinants of assortative mating, and for historical reasons are correlated with the amount of Indian blood. As a consequence, the Indian and Spanish gene pools are still quite distinct despite 400 years of socially limited gene flow. Another example is provided by whites & blacks in the US vs. N.E. Brazil. In North Amer., European settlers imported black slaves mainly from , with 98% of them coming from West and West- Central Africa. There is a strong tendency for assortative mating on racial category, but when hybrids are formed, they are socially classified as blacks. (Genetically, and phenotypically, the hybrids are intermediate and are no more "black" than they are "white".) This social definition of hybrids as "black" when coupled with assortative mating by racial category and the numerical predominance of "whites" results in a very asymetrical gene flow pattern. Effectively, almost all gene flow is from whites into blacks, with almost none going in the other direction. Let M = the effective amount of gene flow over the entire relevant period of North American history (in
3 contrast to m, which was a per generation gene flow parameter). Then we can model the North Amer. situation as follows: European West African p a 1 M 1-M p b =M +(1-M)p a Given the allele frequencies, you can estimate M by M = (p b -p a )/( -p a ) e.g., for the Rh + allele, p b =.4381, p a =.5512, and =.0279, so M=.216. In the U.S., estimates of M range from 3% (S.C.) to 27% (Detroit). In the northeast of Brazil, the social definition of hybrids is "white". Hence, NE Brazil had the opposite pattern of gene flow: European West African p a 1-M M 1 =Mp a +(1-M) p a Because the blacks were a minority in Brazil as well, this pattern of gene flow means that most N.E. Brazilians are of mixed European/African ancestry. Eg., in
4 Northeastern Brazil, the white gene pool is 59% European, 30% African, and 11% Indian. Similarly, can characterize people on basis of skin color from "Most Caucasoid" to "Most Negroid". In US., "most caucasoid" group is about 100% European in origin, and the average "black" about 20% European. In N.E. Brazil, the most Caucasoid group is 71% European, and most Negroid 28%. Thus, the social definitions used in system of mating in the two countries have had a major genetic impact on the composition of their present day populations dispite similar initial conditions. The Genetic Impact of Gene Flow We have already seen that allele frequencies are altered when gene flow occurs between genetically distinct populations. But the alterations are in a specific direction. Let d = p 2. Recall that ' = (1-m) + mp 2 = - m( -p 2 ) = - md p 2 ' = p 2 + md Hence ' - p 2 ' = d' = - md - p 2 -md = d(1-2m) < d for all m>0. After t generations: d t = d(1-2m) t 0 as t. Therefore, GENE FLOW DECREASES GENETIC VARIABILITY BETWEEN POPULATIONS. However, recall that, like mutation, GENE FLOW CAN INTRODUCE NEW ALLELES INTO A POPULATION, AND THEREFORE GENE FLOW INCREASES GENETIC VARIABILITY WITHIN A POPULATION. VERY IMPORTANT -- THE EFFECTS OF GENE FLOW ON WITHIN AND BETWEEN POPULATION GENETIC VARIABILITY ARE THE OPPOSITE OF THOSE OF GENETIC DRIFT. THEREFORE, THE BALANCE BETWEEN DRIFT AND GENE FLOW IS THE PRIMARY DETERMINANT OF THE GENETIC POPULATION STRUCTURE OF A SPECIES. Genetic population structure refers to 1) how genetic variability is distributed within a species (within and between local populations), and 2) how genetic variability in gene pools is related to individual level genotypic variability (this is also highly dependent upon the system of mating). Genetic and genotypic variability provide the raw material for all evolutionary change, including that caused by natural selection. As will be seen later, natural selection operates within the constraints imposed by the genetic structure.
5 The Balance of Gene Flow and Drift Recall that to measure the impact of genetic drift upon identity by descent, we started with the equation: = 1/(2N ef To examine the balance between drift and mutation, we modified the above equation as follows: = {1/(2N ef }(1-µ) 2 A similar modification can be used to address the following question: suppose two populations of inbreeding effective size N ef are experiencing gene flow at a rate of m per generation. Then, what is the probabilty that two randomly drawn genes from the same subpopulation are identical by descent AND from the same population? That is, if one of the genes came from the other gene pool, we no longer regard it as identical. The equation for this probability is then: = {1/(2N ef }(1-m) 2 which at equilibrium yields F eq 1/(4N ef m + 1) if m is small. These results emphasize the similar impact of gene flow and mutation, as discussed above. This can also be interpreted in the coalescent sense as the probability that two genes randomly drawn from the same subpopulation coalescece back to a common ancestor before either lineage experienced a gene flow even given than either coalescence or gene flow has occurred. This equilibrium equation reflects the balance of gene flow (proportional to m) vs. drift (proportional to 1/N ef ) as measured by their ratio [m/(1/n ef ) = N ef m] upon identity by descent within a subpopulation when alleles drawn from outside are regarded as nonidentical. Wright therefore defined this F as F st where the st designates this as identity by descent in the subpopulation with regard to the t otal population. (Note, just as drift influences both ibd and variances of allele frequencies, resulting in more than one effective size, there is also an alternative definition of F st in terms of variances of allele frequencies, as will be given in the next handout.) As expected, as m goes up, F st goes down, as 1/N ef goes up (drift goes up), F st goes up. What is surprising is how little gene flow is needed to cause two populations to behave effectively as a single evolutionary lineage. E.g., let N ef m =1, that is, one effective migrant per generation. Then, F st = 1/5 =.20. That is, 80% of the gene pairs drawn from the same subpopulation will show gene flow before coalescence (that is, the genes travelled through different geographical areas before they coalesced). The other thing that is surprising is that the proportion of genes shared
6 by two populations as measured by 1-F st depends only upon the effective number of migrants (N ef m) and not the rate of gene flow (m). For example, two subpopulations of a billion each whould share 80% of their genes by exchanging only 1 individual per generation, as would two subpopulations of size 100. The reason why the same number of migrants is needed for a particular level of F st and not the same rate of gene flow is that F st represents a balance between the rate at which gene flow causes subpopulations to diverge vs. the rate at which gene flow makes them more similar. In large populations, divergence is slow, so small amounts of gene flow are effective in counterbalancing divergence; as populations because smaller, larger and larger rates of gene flow are needed to counterbalance the increasing rate of divergence. Similarly, it is the product N ef m (which reflects the balance of drift vs. gene flow) and not m that determines the relative coalescence times of genes within and among local populations. If there is restricted gene flow among demes, it makes sense that the average time to coalescence (a common DNA molecule) for two genes sampled within a deme will be less than that for two genes sampled at random for the entire species. In particular, Slatkin (Genet. Res. 58: , 1991) has shown that these relative times are determined by N ef m. The exact relationship depends upon the pattern of gene flow, but consider the simple island model case of a species subdivided into a large number of local demes each of size N ef and each receiving m of its genes per generation from the species at large. Then, N ef m = where t 0 t 0 4 ( t t 0 ) = the average time to coalescence of two genes sampled from the same deme and t = the average time to coalescence of two genes sampled from the entire species Hence, the ratio of within deme coalescence time to entire species coalescence time is: t 0 t = 4 N ef m N ef m For example, the ratio of coalescence times of Y chromosomes in East Anglia, UK to humans globally has been estimated to be between 0.56 and 0.71 (Cooper et al. Human Molecular Genetics 5, , 1996). This yields an N ef m for Y chromosomes of between 1.22 and 0.64 for humans (note, 2N ef m appears in the ratio equation in this case and not 4N ef m because Y-DNA is haploid). Likewise, F st now has a simple interpretation in terms of coalescence times:
7 F st = t t o t or t o t = 1 F st In general, there is a lack of appreciation over just how little gene flow is needed to keep populations evolving together as a single unit. For example, F st.15 when the major racial groups of humans are regarded as the subpopulations. This could be explained by only a little more than one effective migrant per generation (1.42) among the races over recent the evolutionary history of humans (a result consistent with coalescent times of Y-DNA -- recall that N ef for Y DNA refers only to males). Likewise, one can convert this F st into the relative coalescence times of genes within races versus humans as an entire species such that the average coalescence time of two genes drawn from within a race is 85% of that for 2 genes randomly drawn from humanity as a whole. Thus, it does not take a lot of exchange between the races to insure that humans evolve as a single evolutionary lineage. This fact is not widely appreciated, as evidenced by the debates over the out-of-africa replacement vs. the multiregional hypotheses concerning the origins of the modern races. The Balance of Gene Flow, Mutation, and Drift If we regard that ibd can be destroyed by both mutation and gene flow, then the appropriate balance equation is: = {1/(2N ef }[(1-µ)(1-m)] 2 If both µ and m are small, then using a Taylor s series, (1-µ)(1-m) 1-µ-m. Hence, F eq 1/[4N ef (µ+m) + 1]. The above equation emphasizes the similar role that the disparate forces of mutation and gene flow have upon genetic variation and identity by descent.
Biology 1406 - Notes for exam 5 - Population genetics Ch 13, 14, 15
Biology 1406 - Notes for exam 5 - Population genetics Ch 13, 14, 15 Species - group of individuals that are capable of interbreeding and producing fertile offspring; genetically similar 13.7, 14.2 Population
More informationBasic Principles of Forensic Molecular Biology and Genetics. Population Genetics
Basic Principles of Forensic Molecular Biology and Genetics Population Genetics Significance of a Match What is the significance of: a fiber match? a hair match? a glass match? a DNA match? Meaning of
More informationSummary. 16 1 Genes and Variation. 16 2 Evolution as Genetic Change. Name Class Date
Chapter 16 Summary Evolution of Populations 16 1 Genes and Variation Darwin s original ideas can now be understood in genetic terms. Beginning with variation, we now know that traits are controlled by
More informationContinuous and discontinuous variation
Continuous and discontinuous variation Variation, the small differences that exist between individuals, can be described as being either discontinuous or continuous. Discontinuous variation This is where
More informationPrinciples of Evolution - Origin of Species
Theories of Organic Evolution X Multiple Centers of Creation (de Buffon) developed the concept of "centers of creation throughout the world organisms had arisen, which other species had evolved from X
More informationPRINCIPLES OF POPULATION GENETICS
PRINCIPLES OF POPULATION GENETICS FOURTH EDITION Daniel L. Hartl Harvard University Andrew G. Clark Cornell University UniversitSts- und Landesbibliothek Darmstadt Bibliothek Biologie Sinauer Associates,
More informationChapter 9 Patterns of Inheritance
Bio 100 Patterns of Inheritance 1 Chapter 9 Patterns of Inheritance Modern genetics began with Gregor Mendel s quantitative experiments with pea plants History of Heredity Blending theory of heredity -
More informationEvolution (18%) 11 Items Sample Test Prep Questions
Evolution (18%) 11 Items Sample Test Prep Questions Grade 7 (Evolution) 3.a Students know both genetic variation and environmental factors are causes of evolution and diversity of organisms. (pg. 109 Science
More informationMendelian and Non-Mendelian Heredity Grade Ten
Ohio Standards Connection: Life Sciences Benchmark C Explain the genetic mechanisms and molecular basis of inheritance. Indicator 6 Explain that a unit of hereditary information is called a gene, and genes
More informationOkami Study Guide: Chapter 3 1
Okami Study Guide: Chapter 3 1 Chapter in Review 1. Heredity is the tendency of offspring to resemble their parents in various ways. Genes are units of heredity. They are functional strands of DNA grouped
More informationHeredity. Sarah crosses a homozygous white flower and a homozygous purple flower. The cross results in all purple flowers.
Heredity 1. Sarah is doing an experiment on pea plants. She is studying the color of the pea plants. Sarah has noticed that many pea plants have purple flowers and many have white flowers. Sarah crosses
More informationLecture 10 Friday, March 20, 2009
Lecture 10 Friday, March 20, 2009 Reproductive isolating mechanisms Prezygotic barriers: Anything that prevents mating and fertilization is a prezygotic mechanism. Habitat isolation, behavioral isolation,
More informationEvolution, Natural Selection, and Adaptation
Evolution, Natural Selection, and Adaptation Nothing in biology makes sense except in the light of evolution. (Theodosius Dobzhansky) Charles Darwin (1809-1882) Voyage of HMS Beagle (1831-1836) Thinking
More informationThe Concept of Inclusive Fitness 1 Ethology and Behavioral Ecology Spring 2008
The Concept of Inclusive Fitness 1 Ethology and Behavioral Ecology Spring 2008 I. The components of Fitness A. Direct fitness W d, darwinian fitness, W gained by increasing ones own reproduction relative
More informationGenetics 1. Defective enzyme that does not make melanin. Very pale skin and hair color (albino)
Genetics 1 We all know that children tend to resemble their parents. Parents and their children tend to have similar appearance because children inherit genes from their parents and these genes influence
More informationMechanisms of Evolution
page 2 page 3 Teacher's Notes Mechanisms of Evolution Grades: 11-12 Duration: 28 mins Summary of Program Evolution is the gradual change that can be seen in a population s genetic composition, from one
More informationBayesian coalescent inference of population size history
Bayesian coalescent inference of population size history Alexei Drummond University of Auckland Workshop on Population and Speciation Genomics, 2016 1st February 2016 1 / 39 BEAST tutorials Population
More informationName: 4. A typical phenotypic ratio for a dihybrid cross is a) 9:1 b) 3:4 c) 9:3:3:1 d) 1:2:1:2:1 e) 6:3:3:6
Name: Multiple-choice section Choose the answer which best completes each of the following statements or answers the following questions and so make your tutor happy! 1. Which of the following conclusions
More information5 GENETIC LINKAGE AND MAPPING
5 GENETIC LINKAGE AND MAPPING 5.1 Genetic Linkage So far, we have considered traits that are affected by one or two genes, and if there are two genes, we have assumed that they assort independently. However,
More informationGene Mapping Techniques
Gene Mapping Techniques OBJECTIVES By the end of this session the student should be able to: Define genetic linkage and recombinant frequency State how genetic distance may be estimated State how restriction
More informationHeredity - Patterns of Inheritance
Heredity - Patterns of Inheritance Genes and Alleles A. Genes 1. A sequence of nucleotides that codes for a special functional product a. Transfer RNA b. Enzyme c. Structural protein d. Pigments 2. Genes
More informationAP Biology Essential Knowledge Student Diagnostic
AP Biology Essential Knowledge Student Diagnostic Background The Essential Knowledge statements provided in the AP Biology Curriculum Framework are scientific claims describing phenomenon occurring in
More informationGenetics Lecture Notes 7.03 2005. Lectures 1 2
Genetics Lecture Notes 7.03 2005 Lectures 1 2 Lecture 1 We will begin this course with the question: What is a gene? This question will take us four lectures to answer because there are actually several
More informationChapter 13: Meiosis and Sexual Life Cycles
Name Period Chapter 13: Meiosis and Sexual Life Cycles Concept 13.1 Offspring acquire genes from parents by inheriting chromosomes 1. Let s begin with a review of several terms that you may already know.
More informationPractice Problems 4. (a) 19. (b) 36. (c) 17
Chapter 10 Practice Problems Practice Problems 4 1. The diploid chromosome number in a variety of chrysanthemum is 18. What would you call varieties with the following chromosome numbers? (a) 19 (b) 36
More informationA Hands-On Exercise To Demonstrate Evolution
HOW-TO-DO-IT A Hands-On Exercise To Demonstrate Evolution by Natural Selection & Genetic Drift H ELEN J. YOUNG T RUMAN P. Y OUNG Although students learn (i.e., hear about) the components of evolution by
More informationBiology Behind the Crime Scene Week 4: Lab #4 Genetics Exercise (Meiosis) and RFLP Analysis of DNA
Page 1 of 5 Biology Behind the Crime Scene Week 4: Lab #4 Genetics Exercise (Meiosis) and RFLP Analysis of DNA Genetics Exercise: Understanding how meiosis affects genetic inheritance and DNA patterns
More informationAP BIOLOGY 2010 SCORING GUIDELINES (Form B)
AP BIOLOGY 2010 SCORING GUIDELINES (Form B) Question 2 Certain human genetic conditions, such as sickle cell anemia, result from single base-pair mutations in DNA. (a) Explain how a single base-pair mutation
More informationBasics of Marker Assisted Selection
asics of Marker ssisted Selection Chapter 15 asics of Marker ssisted Selection Julius van der Werf, Department of nimal Science rian Kinghorn, Twynam Chair of nimal reeding Technologies University of New
More informationInvestigating the genetic basis for intelligence
Investigating the genetic basis for intelligence Steve Hsu University of Oregon and BGI www.cog-genomics.org Outline: a multidisciplinary subject 1. What is intelligence? Psychometrics 2. g and GWAS: a
More informationGENOMIC SELECTION: THE FUTURE OF MARKER ASSISTED SELECTION AND ANIMAL BREEDING
GENOMIC SELECTION: THE FUTURE OF MARKER ASSISTED SELECTION AND ANIMAL BREEDING Theo Meuwissen Institute for Animal Science and Aquaculture, Box 5025, 1432 Ås, Norway, theo.meuwissen@ihf.nlh.no Summary
More informationAfrican Ancestry of the White American Population
The Ohio State University Knowledge Bank kb.osu.edu Ohio Journal of Science (Ohio Academy of Science) Ohio Journal of Science: Volume 58, Issue 3 (May, 1958) 1958-05 African Ancestry of the White American
More informationPaternity Testing. Chapter 23
Paternity Testing Chapter 23 Kinship and Paternity DNA analysis can also be used for: Kinship testing determining whether individuals are related Paternity testing determining the father of a child Missing
More informationPopulation Genetics and Multifactorial Inheritance 2002
Population Genetics and Multifactorial Inheritance 2002 Consanguinity Genetic drift Founder effect Selection Mutation rate Polymorphism Balanced polymorphism Hardy-Weinberg Equilibrium Hardy-Weinberg Equilibrium
More informationHardy-Weinberg Equilibrium Problems
Hardy-Weinberg Equilibrium Problems 1. The frequency of two alleles in a gene pool is 0.19 (A) and 0.81(a). Assume that the population is in Hardy-Weinberg equilibrium. (a) Calculate the percentage of
More informationThe Human Genome. Genetics and Personality. The Human Genome. The Human Genome 2/19/2009. Chapter 6. Controversy About Genes and Personality
The Human Genome Chapter 6 Genetics and Personality Genome refers to the complete set of genes that an organism possesses Human genome contains 30,000 80,000 genes on 23 pairs of chromosomes The Human
More informationSimulation Model of Mating Behavior in Flies
Simulation Model of Mating Behavior in Flies MEHMET KAYIM & AYKUT Ecological and Evolutionary Genetics Lab. Department of Biology, Middle East Technical University International Workshop on Hybrid Systems
More informationTerms: The following terms are presented in this lesson (shown in bold italics and on PowerPoint Slides 2 and 3):
Unit B: Understanding Animal Reproduction Lesson 4: Understanding Genetics Student Learning Objectives: Instruction in this lesson should result in students achieving the following objectives: 1. Explain
More informationHUMAN SKIN COLOR: EVIDENCE FOR SELECTION
OVERVIEW HUMAN SKIN COLOR: EVIDENCE FOR SELECTION This activity supports the viewing of the short film The Biology of Skin Color. Students watch the film in segments and use real data to propose hypotheses,
More informationSection 1.3 P 1 = 1 2. = 1 4 2 8. P n = 1 P 3 = Continuing in this fashion, it should seem reasonable that, for any n = 1, 2, 3,..., = 1 2 4.
Difference Equations to Differential Equations Section. The Sum of a Sequence This section considers the problem of adding together the terms of a sequence. Of course, this is a problem only if more than
More informationY Chromosome Markers
Y Chromosome Markers Lineage Markers Autosomal chromosomes recombine with each meiosis Y and Mitochondrial DNA does not This means that the Y and mtdna remains constant from generation to generation Except
More informationTrasposable elements: P elements
Trasposable elements: P elements In 1938 Marcus Rhodes provided the first genetic description of an unstable mutation, an allele of a gene required for the production of pigment in maize. This instability
More information7 POPULATION GENETICS
7 POPULATION GENETICS 7.1 INTRODUCTION Most humans are susceptible to HIV infection. However, some people seem to be able to avoid infection despite repeated exposure. Some resistance is due to a rare
More informationAP: LAB 8: THE CHI-SQUARE TEST. Probability, Random Chance, and Genetics
Ms. Foglia Date AP: LAB 8: THE CHI-SQUARE TEST Probability, Random Chance, and Genetics Why do we study random chance and probability at the beginning of a unit on genetics? Genetics is the study of inheritance,
More informationForensic DNA Testing Terminology
Forensic DNA Testing Terminology ABI 310 Genetic Analyzer a capillary electrophoresis instrument used by forensic DNA laboratories to separate short tandem repeat (STR) loci on the basis of their size.
More informationChapter 13: Meiosis and Sexual Life Cycles
Name Period Concept 13.1 Offspring acquire genes from parents by inheriting chromosomes 1. Let s begin with a review of several terms that you may already know. Define: gene locus gamete male gamete female
More informationBiological Sciences Initiative. Human Genome
Biological Sciences Initiative HHMI Human Genome Introduction In 2000, researchers from around the world published a draft sequence of the entire genome. 20 labs from 6 countries worked on the sequence.
More informationA and B are not absolutely linked. They could be far enough apart on the chromosome that they assort independently.
Name Section 7.014 Problem Set 5 Please print out this problem set and record your answers on the printed copy. Answers to this problem set are to be turned in to the box outside 68-120 by 5:00pm on Friday
More informationA trait is a variation of a particular character (e.g. color, height). Traits are passed from parents to offspring through genes.
1 Biology Chapter 10 Study Guide Trait A trait is a variation of a particular character (e.g. color, height). Traits are passed from parents to offspring through genes. Genes Genes are located on chromosomes
More informationAS Biology Unit 2 Key Terms and Definitions. Make sure you use these terms when answering exam questions!
AS Biology Unit 2 Key Terms and Definitions Make sure you use these terms when answering exam questions! Chapter 7 Variation 7.1 Random Sampling Sampling a population to eliminate bias e.g. grid square
More informationCCR Biology - Chapter 7 Practice Test - Summer 2012
Name: Class: Date: CCR Biology - Chapter 7 Practice Test - Summer 2012 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. A person who has a disorder caused
More informationCHROMOSOMES AND INHERITANCE
SECTION 12-1 REVIEW CHROMOSOMES AND INHERITANCE VOCABULARY REVIEW Distinguish between the terms in each of the following pairs of terms. 1. sex chromosome, autosome 2. germ-cell mutation, somatic-cell
More informationList, describe, diagram, and identify the stages of meiosis.
Meiosis and Sexual Life Cycles In this topic we will examine a second type of cell division used by eukaryotic cells: meiosis. In addition, we will see how the 2 types of eukaryotic cell division, mitosis
More informationMitosis, Meiosis and Fertilization 1
Mitosis, Meiosis and Fertilization 1 I. Introduction When you fall and scrape the skin off your hands or knees, how does your body make new skin cells to replace the skin cells that were scraped off? How
More informationBiology 1406 Exam 4 Notes Cell Division and Genetics Ch. 8, 9
Biology 1406 Exam 4 Notes Cell Division and Genetics Ch. 8, 9 Ch. 8 Cell Division Cells divide to produce new cells must pass genetic information to new cells - What process of DNA allows this? Two types
More informationHLA data analysis in anthropology: basic theory and practice
HLA data analysis in anthropology: basic theory and practice Alicia Sanchez-Mazas and José Manuel Nunes Laboratory of Anthropology, Genetics and Peopling history (AGP), Department of Anthropology and Ecology,
More information1. Why is mitosis alone insufficient for the life cycle of sexually reproducing eukaryotes?
Chapter 13: Meiosis and Sexual Life Cycles 1. Why is mitosis alone insufficient for the life cycle of sexually reproducing eukaryotes? 2. Define: gamete zygote meiosis homologous chromosomes diploid haploid
More informationComparison of Major Domination Schemes for Diploid Binary Genetic Algorithms in Dynamic Environments
Comparison of Maor Domination Schemes for Diploid Binary Genetic Algorithms in Dynamic Environments A. Sima UYAR and A. Emre HARMANCI Istanbul Technical University Computer Engineering Department Maslak
More informationChapter 8: Recombinant DNA 2002 by W. H. Freeman and Company Chapter 8: Recombinant DNA 2002 by W. H. Freeman and Company
Genetic engineering: humans Gene replacement therapy or gene therapy Many technical and ethical issues implications for gene pool for germ-line gene therapy what traits constitute disease rather than just
More informationPopstats Unplugged. 14 th International Symposium on Human Identification. John V. Planz, Ph.D. UNT Health Science Center at Fort Worth
Popstats Unplugged 14 th International Symposium on Human Identification John V. Planz, Ph.D. UNT Health Science Center at Fort Worth Forensic Statistics From the ground up Why so much attention to statistics?
More informationChapter 4 The role of mutation in evolution
Chapter 4 The role of mutation in evolution Objective Darwin pointed out the importance of variation in evolution. Without variation, there would be nothing for natural selection to act upon. Any change
More informationI. Genes found on the same chromosome = linked genes
Genetic recombination in Eukaryotes: crossing over, part 1 I. Genes found on the same chromosome = linked genes II. III. Linkage and crossing over Crossing over & chromosome mapping I. Genes found on the
More informationGenetics for the Novice
Genetics for the Novice by Carol Barbee Wait! Don't leave yet. I know that for many breeders any article with the word genetics in the title causes an immediate negative reaction. Either they quickly turn
More informationMendelian inheritance and the
Mendelian inheritance and the most common genetic diseases Cornelia Schubert, MD, University of Goettingen, Dept. Human Genetics EUPRIM-Net course Genetics, Immunology and Breeding Mangement German Primate
More informationLAB : THE CHI-SQUARE TEST. Probability, Random Chance, and Genetics
Period Date LAB : THE CHI-SQUARE TEST Probability, Random Chance, and Genetics Why do we study random chance and probability at the beginning of a unit on genetics? Genetics is the study of inheritance,
More information12.1 The Role of DNA in Heredity
12.1 The Role of DNA in Heredity Only in the last 50 years have scientists understood the role of DNA in heredity. That understanding began with the discovery of DNA s structure. In 1952, Rosalind Franklin
More informationGenetics and Evolution: An ios Application to Supplement Introductory Courses in. Transmission and Evolutionary Genetics
G3: Genes Genomes Genetics Early Online, published on April 11, 2014 as doi:10.1534/g3.114.010215 Genetics and Evolution: An ios Application to Supplement Introductory Courses in Transmission and Evolutionary
More informationLitteratur. Lärandemål för undervisningstillfälle. Lecture Overview. Basic principles The twin design The adoption design
Litteratur Behavioral Genetics Twin and Adoptions studies Twin and adoption methods (Kapitel 5; sid 70-91) Henrik Larsson MEB Lärandemål för undervisningstillfälle - Studenten ska kunna redogöra för kvantitativa-genetiska
More informationLAB 11 Drosophila Genetics
LAB 11 Drosophila Genetics Introduction: Drosophila melanogaster, the fruit fly, is an excellent organism for genetics studies because it has simple food requirements, occupies little space, is hardy,
More informationIntroduction. What is Ecological Genetics?
1 Introduction What is Ecological enetics? Ecological genetics is at the interface of ecology, evolution, and genetics, and thus includes important elements from each of these fields. We can use two closely
More informationLecture 6: Single nucleotide polymorphisms (SNPs) and Restriction Fragment Length Polymorphisms (RFLPs)
Lecture 6: Single nucleotide polymorphisms (SNPs) and Restriction Fragment Length Polymorphisms (RFLPs) Single nucleotide polymorphisms or SNPs (pronounced "snips") are DNA sequence variations that occur
More informationUnderstanding by Design. Title: BIOLOGY/LAB. Established Goal(s) / Content Standard(s): Essential Question(s) Understanding(s):
Understanding by Design Title: BIOLOGY/LAB Standard: EVOLUTION and BIODIVERSITY Grade(s):9/10/11/12 Established Goal(s) / Content Standard(s): 5. Evolution and Biodiversity Central Concepts: Evolution
More informationAsexual Versus Sexual Reproduction in Genetic Algorithms 1
Asexual Versus Sexual Reproduction in Genetic Algorithms Wendy Ann Deslauriers (wendyd@alumni.princeton.edu) Institute of Cognitive Science,Room 22, Dunton Tower Carleton University, 25 Colonel By Drive
More informationElsevier Editorial System(tm) for Forensic Science International: Genetics Manuscript Draft
Elsevier Editorial System(tm) for Forensic Science International: Genetics Manuscript Draft Manuscript Number: Title: A comment on the Paper: A comparison of Y-chromosomal lineage dating using either resequencing
More informationName Class Date. binomial nomenclature. MAIN IDEA: Linnaeus developed the scientific naming system still used today.
Section 1: The Linnaean System of Classification 17.1 Reading Guide KEY CONCEPT Organisms can be classified based on physical similarities. VOCABULARY taxonomy taxon binomial nomenclature genus MAIN IDEA:
More informationBCOR101 Midterm II Wednesday, October 26, 2005
BCOR101 Midterm II Wednesday, October 26, 2005 Name Key Please show all of your work. 1. A donor strain is trp+, pro+, met+ and a recipient strain is trp-, pro-, met-. The donor strain is infected with
More informationPractice Questions 1: Evolution
Practice Questions 1: Evolution 1. Which concept is best illustrated in the flowchart below? A. natural selection B. genetic manipulation C. dynamic equilibrium D. material cycles 2. The diagram below
More informationEvolution by Natural Selection 1
Evolution by Natural Selection 1 I. Mice Living in a Desert These drawings show how a population of mice on a beach changed over time. 1. Describe how the population of mice is different in figure 3 compared
More informationChromosomes, Mapping, and the Meiosis Inheritance Connection
Chromosomes, Mapping, and the Meiosis Inheritance Connection Carl Correns 1900 Chapter 13 First suggests central role for chromosomes Rediscovery of Mendel s work Walter Sutton 1902 Chromosomal theory
More informationTwo-locus population genetics
Two-locus population genetics Introduction So far in this course we ve dealt only with variation at a single locus. There are obviously many traits that are governed by more than a single locus in whose
More informationDeterministic computer simulations were performed to evaluate the effect of maternallytransmitted
Supporting Information 3. Host-parasite simulations Deterministic computer simulations were performed to evaluate the effect of maternallytransmitted parasites on the evolution of sex. Briefly, the simulations
More informationThis commentary was written for the Qb by Martin Bulmer, 1999
Question bank Commentary: Ethnicity This commentary was written for the Qb by Martin Bulmer, 1999 Should you wish to cite any commentary in the topics section, please use the following format: Crispin
More informationSexual Reproduction. The specialized cells that are required for sexual reproduction are known as. And come from the process of: GAMETES
Sexual Reproduction Sexual Reproduction We know all about asexual reproduction 1. Only one parent required. 2. Offspring are identical to parents. 3. The cells that produce the offspring are not usually
More informationGenetics 301 Sample Final Examination Spring 2003
Genetics 301 Sample Final Examination Spring 2003 50 Multiple Choice Questions-(Choose the best answer) 1. A cross between two true breeding lines one with dark blue flowers and one with bright white flowers
More informationExploring contact patterns between two subpopulations
Exploring contact patterns between two subpopulations Winfried Just Hannah Callender M. Drew LaMar December 23, 2015 In this module 1 we introduce a construction of generic random graphs for a given degree
More informationSample Size and Power in Clinical Trials
Sample Size and Power in Clinical Trials Version 1.0 May 011 1. Power of a Test. Factors affecting Power 3. Required Sample Size RELATED ISSUES 1. Effect Size. Test Statistics 3. Variation 4. Significance
More informationThe Developing Person Through the Life Span 8e by Kathleen Stassen Berger
The Developing Person Through the Life Span 8e by Kathleen Stassen Berger Chapter 3 Heredity and Environment PowerPoint Slides developed by Martin Wolfger and Michael James Ivy Tech Community College-Bloomington
More informationName: Class: Date: ID: A
Name: Class: _ Date: _ Meiosis Quiz 1. (1 point) A kidney cell is an example of which type of cell? a. sex cell b. germ cell c. somatic cell d. haploid cell 2. (1 point) How many chromosomes are in a human
More informationLecture 3: Mutations
Lecture 3: Mutations Recall that the flow of information within a cell involves the transcription of DNA to mrna and the translation of mrna to protein. Recall also, that the flow of information between
More informationFAQs: Gene drives - - What is a gene drive?
FAQs: Gene drives - - What is a gene drive? During normal sexual reproduction, each of the two versions of a given gene has a 50 percent chance of being inherited by a particular offspring (Fig 1A). Gene
More information(1-p) 2. p(1-p) From the table, frequency of DpyUnc = ¼ (p^2) = #DpyUnc = p^2 = 0.0004 ¼(1-p)^2 + ½(1-p)p + ¼(p^2) #Dpy + #DpyUnc
Advanced genetics Kornfeld problem set_key 1A (5 points) Brenner employed 2-factor and 3-factor crosses with the mutants isolated from his screen, and visually assayed for recombination events between
More informationA Diffusion Wave out of Africa
Current Anthropology Volume 43, Number 5, December 2002 2002 by The Wenner-Gren Foundation for Anthropological Research. All rights reserved 0011-3204/2002/4305-0003$3.00 A Diffusion Wave out of Africa
More informationLESSON 3.5 WORKBOOK. How do cancer cells evolve? Workbook Lesson 3.5
LESSON 3.5 WORKBOOK How do cancer cells evolve? In this unit we have learned how normal cells can be transformed so that they stop behaving as part of a tissue community and become unresponsive to regulation.
More informationBioSci 2200 General Genetics Problem Set 1 Answer Key Introduction and Mitosis/ Meiosis
BioSci 2200 General Genetics Problem Set 1 Answer Key Introduction and Mitosis/ Meiosis Introduction - Fields of Genetics To answer the following question, review the three traditional subdivisions of
More informationIntroduction to Physical Anthropology - Study Guide - Focus Topics
Introduction to Physical Anthropology - Study Guide - Focus Topics Chapter 1 Species: Recognize all definitions. Evolution: Describe all processes. Culture: Define and describe importance. Biocultural:
More informationBiology Final Exam Study Guide: Semester 2
Biology Final Exam Study Guide: Semester 2 Questions 1. Scientific method: What does each of these entail? Investigation and Experimentation Problem Hypothesis Methods Results/Data Discussion/Conclusion
More information1) Write the following as an algebraic expression using x as the variable: Triple a number subtracted from the number
1) Write the following as an algebraic expression using x as the variable: Triple a number subtracted from the number A. 3(x - x) B. x 3 x C. 3x - x D. x - 3x 2) Write the following as an algebraic expression
More informationIncomplete Dominance and Codominance
Name: Date: Period: Incomplete Dominance and Codominance 1. In Japanese four o'clock plants red (R) color is incompletely dominant over white (r) flowers, and the heterozygous condition (Rr) results in
More informationStatistical tests for SPSS
Statistical tests for SPSS Paolo Coletti A.Y. 2010/11 Free University of Bolzano Bozen Premise This book is a very quick, rough and fast description of statistical tests and their usage. It is explicitly
More informationCommonly Used STR Markers
Commonly Used STR Markers Repeats Satellites 100 to 1000 bases repeated Minisatellites VNTR variable number tandem repeat 10 to 100 bases repeated Microsatellites STR short tandem repeat 2 to 6 bases repeated
More information