• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Chapter 21~The Evolution of Populations
Chapter 21~The Evolution of Populations

...  Evolution Natural selection acts on trait variation, and trait variation is determined by genes. Whether or not a trait gives an advantage depends on the environment. Thus genes, traits, environment, and natural selection are all involved in microevolution.  Microevolution occurs when allele fre ...
File - Groby Bio Page
File - Groby Bio Page

... involved they act in an epistatic way where one gene masks or influences another ...
Forces of Microevolution Examples
Forces of Microevolution Examples

... 4. Human babies that are too small at birth are weak and often die. Human babies that are too large cannot fit through the birth canal and mother/child die. What is this an example of? (Stabilizing selection, one outcome of natural selection) 5. A small group of Amish people moved from Europe to Lan ...
Introducing Variation
Introducing Variation

... differences in traits between individual organisms. The combination of alleles from the father and the mother results in a unique genetic combination. This unique combination of alleles in each individual creates species diversity. This variation in the DNA code is found in the genes on chromosomes. ...
Chapter 4 Heredity and Evolution
Chapter 4 Heredity and Evolution

... or are remnants of, larger populations. A new population will be established, and as long as mates are chosen only within this population, all the members will be descended from the founders. An allele that was rare in the founders’ parent population but is carried by even one of ...
3-HumanGen Linkage
3-HumanGen Linkage

... genes is used to construct LINKAGE MAPS (Chromosome Maps). • Crossing-over occurs more often between some alleles than between others. – Since most alleles occupy a fixed place on a chromosome. ...
WORKING WITH THE FIGURES
WORKING WITH THE FIGURES

... Answer: The phenotypic variance of the trait does not appear to have changed as a result of selection. Neither the range nor the shape of the phenotypic distribution have changed, so the variance would not have changed because it is a function of these two parameters. Although it might be expected t ...
Evolution of Populations
Evolution of Populations

... much quantitative effect on a large population in a single generation. An individual mutant allele may have greater impacts later through increases in its relative frequencies as a result of natural selection or genetic drift. ...
MetaQuant : a new platform dealing with DNA samples
MetaQuant : a new platform dealing with DNA samples

... Hayashi 2002 Tannock 2000 Suau 1999 ...
The Human Genome
The Human Genome

... • The weaker allele not expressed is the “recessive” allele. Though not expressed, it is part of your “genotype” & can be passed on to your kids. Recessive trait is usually only expressed when you inherit the recessive allele from both parents. • Dominant alleles indicated by upper-case letters • Mo ...
Jeremy Gruber - PowerPoint - Personlaized Medicine
Jeremy Gruber - PowerPoint - Personlaized Medicine

... Large Gap Remains Between Research and Clinical Applications ...
Standard 9: The Genetics of Life Study Guide PART 1: Basic
Standard 9: The Genetics of Life Study Guide PART 1: Basic

... 11. Which pair of sex chromosomes makes a person a male: XX or XY? 12. What is the difference between incomplete dominance and co dominance? ______________________________________ ...
Population Genetics in the Post
Population Genetics in the Post

... •Haplotypes make a SNP map of the human genome redundant: as some SNPs will be transmitted together, we only need a subset of SNPs to tag the entire region. •NHGRI launched in October the HapMap project: a description of the set of haplotype blocks and the SNPs that tag them. The HapMap will be valu ...
Mechanisms for Evolution
Mechanisms for Evolution

... The founder effect is a special case of genetic drift The founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population ...
BB30055: Genes and genomes
BB30055: Genes and genomes

... Each piece of genome sequenced at least 10 times to reduce error rate (0.01%) Polymorphisms Sequence variation between individuals (0.1%) To be defined as a polymorphism, the altered sequence must be present in a significant population ...
zChap00_Front_140901
zChap00_Front_140901

... The first edition of this book was produced in January, 2009 as instructional material for students in Biology 207 at the University of Alberta, and is released to the public for non-commercial use under the Creative Commons License (See below). Users are encouraged to make modifications and improve ...
Population Evolution
Population Evolution

... drift, certain alleles have become fixed while others have been lost completely from the gene pool. ...
Uses and abuses of genetic engineering
Uses and abuses of genetic engineering

... the use of preimplantation genetic diagnosis on the prevention of births involving lethally destructive genetic mutations, as in present HFEA regulations, and to avoid using the procedure for generating children for utilitarian purposes judged beneficial to their parents or their siblings, but which ...
Gene Mutations - Lyndhurst School
Gene Mutations - Lyndhurst School

... desired traits to be the parents of the next generation  This process has been used for hundreds of years  Two Types:  Inbreeding- crossing two individuals that have similar characteristics  Hybridization- crossing two genetically different individuals ...
Biology First Six Weeks Vocabulary
Biology First Six Weeks Vocabulary

... An Austrian monk and botanist who established key principles for the study of genetics; the father of genetics ...
BTEC First Applied Science
BTEC First Applied Science

... You are a scientist working for one of the labs that has taken part in the Human Genome Project. You need to produce an illustrated booklet to explain to the public the importance of the science behind the Human Genome Project. The booklet will describe how genes control the way cells function, and ...
Biological Bases of Behavior
Biological Bases of Behavior

... Why Learn About Biology? • Permits us to see human behavior as having a lot in common with that of other animals. • Considering our biology enables us to see how evolutionary processes have shaped our behavior. • When the biology/brain is disrupted, so is behavior! ...
Genetics Objectives/keywords
Genetics Objectives/keywords

... Genes allow for the storage and transmission of genetic information. They are a set of instructions encoded in the nucleotide sequence of each organism. Genes code for the specific sequences of amino acids that comprise the proteins that are characteristic of that organism. MA Standard 3.4 Distingui ...
Ertertewt ertwetr
Ertertewt ertwetr

... Gene shuffling If you and your siblings have the same parents, and therefore the same genes, why do you look different? Gene shuffling is caused by sexual reproduction. Why do we need two organisms to create life – why not just have all females? Sexual reproduction keeps the genes shuffling and cha ...
Ertertewt ertwetr - Campbell County Schools
Ertertewt ertwetr - Campbell County Schools

... Gene shuffling If you and your siblings have the same parents, and therefore the same genes, why do you look different? Gene shuffling is caused by sexual reproduction. Why do we need two organisms to create life – why not just have all females? Sexual reproduction keeps the genes shuffling and cha ...
< 1 ... 435 436 437 438 439 440 441 442 443 ... 541 >

Human genetic variation



Human genetic variation is the genetic differences both within and among populations. There may be multiple variants of any given gene in the human population (genes), leading to polymorphism. Many genes are not polymorphic, meaning that only a single allele is present in the population: the gene is then said to be fixed. On average, in terms of DNA sequence all humans are 99.9% similar to any other humans.No two humans are genetically identical. Even monozygotic twins, who develop from one zygote, have infrequent genetic differences due to mutations occurring during development and gene copy-number variation. Differences between individuals, even closely related individuals, are the key to techniques such as genetic fingerprinting. Alleles occur at different frequencies in different human populations, with populations that are more geographically and ancestrally remote tending to differ more.Causes of differences between individuals include the exchange of genes during meiosis and various mutational events. There are at least two reasons why genetic variation exists between populations. Natural selection may confer an adaptive advantage to individuals in a specific environment if an allele provides a competitive advantage. Alleles under selection are likely to occur only in those geographic regions where they confer an advantage. The second main cause of genetic variation is due to the high degree of neutrality of most mutations. Most mutations do not appear to have any selective effect one way or the other on the organism. The main cause is genetic drift, this is the effect of random changes in the gene pool. In humans, founder effect and past small population size (increasing the likelihood of genetic drift) may have had an important influence in neutral differences between populations. The theory that humans recently migrated out of Africa supports this.The study of human genetic variation has both evolutionary significance and medical applications. It can help scientists understand ancient human population migrations as well as how different human groups are biologically related to one another. For medicine, study of human genetic variation may be important because some disease-causing alleles occur more often in people from specific geographic regions. New findings show that each human has on average 60 new mutations compared to their parents.Apart from mutations, many genes that may have aided humans in ancient times plague humans today. For example, it is suspected that genes that allow humans to more efficiently process food are those that make people susceptible to obesity and diabetes today.
  • studyres.com © 2026
  • DMCA
  • Privacy
  • Terms
  • Report