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Study Guide
Study Guide

... Can  you  describe  the  relationship  between  phylogeny  and  the  hierarchical  organization  of   variation  in  nature?    How  does  this  relate  to  classification?   I  was  able  to  reconstruct  three  phylogenies  created  by ...
X-Linked Recessive Inheritance
X-Linked Recessive Inheritance

... Why It Matters  Progeria ...
Chapter 11: Intro. to Genetics
Chapter 11: Intro. to Genetics

1 Epistasis Underlying a Fitness Trait within a Natural
1 Epistasis Underlying a Fitness Trait within a Natural

Exclusion of a Role of Hearing Loss
Exclusion of a Role of Hearing Loss

... Exclusion of Cdh23 as a candidate gene in PPI and ASR The present QTL on chromosome 10 spans the cadherin 23 (Cdh23) gene locus and homozygous Cdh23753A (G to A transition at nucleotide 753 in exon 7; this base change causes the in-frame skipping of exon 7) alleles carried by the B6 inbred strain is ...
Mapping Disease Genes
Mapping Disease Genes

... (chromosomal locations), and when the DNA of that region is examined, a gene (transcription unit) is found there, with mutated versions associated with having the disease. – There are several thousand known human genetic diseases with known genes. They are documented at OMIM, the Online Mendelian In ...
Punnett Square Pre-test
Punnett Square Pre-test

PowerPoint 簡報
PowerPoint 簡報

... With all of the seven pea plant traits that Mendel examined, one form appeared dominant over the other. It masked the presence of the other allele. For example, when the genotype for pea color is YG (heterozygous), the phenotype is yellow. However, the dominant yellow allele does not alter the reces ...
Punnett Square Problems
Punnett Square Problems

... Punnett square worksheet (review that for help). Show your work. 1. In humans a gene may help determine if you have dimples; the dominant allele (D) produces dimples, while the recessive allele (d) results in no dimples. Igor has dimples, but his mom does not. He marries Brunhilda, who does not have ...
1.Trait
1.Trait

... independent events will occur together is the product of their individual probabilities  Probability in an F1 monohybrid cross can be determined using the multiplication rule  Segregation in a heterozygous plant is like flipping a coin: Each gamete has a 12 chance of carrying the dominant allele a ...
File - thebiotutor.com
File - thebiotutor.com

... Use your knowledge of natural selection to suggest how this might affect the number of purple and white flowers in the wild. ...
Dihybrid Crosses
Dihybrid Crosses

... Law of Independent Assortment: Alleles of different genes separate independently during gamete formation. Therefore, traits pass to offspring independently of each other. – = The parent makes an equal number of each of the four kind of gametes. A gamete with an allele from one gene does not force it ...
Slide 1
Slide 1

... If we inherit the same allele from both parents our homozygous genotype is ........................ If we inherit different versions of the gene our genotype ...
Slide 1
Slide 1

... • To set up a Punnett Square, decide which trait is dominant • dominant trait = capital letter • recessive trait = lower case letter • homozygous = two capital or two lowercase (PP or pp) • heterozygous = one capital and one ...
Name - Wsfcs
Name - Wsfcs

... 4) Law of Independent Assortment The genes for different traits are inherited independently of each other. Just because you get Dad’s blue eyes doesn’t mean you will get his blonde hair also! Monohybrid Cross Monohybrid Cross - crossing parents who differ in only one trait (TT, Tt, tt) - Use a spe ...
Heterogeneous Reference Populations in Animal
Heterogeneous Reference Populations in Animal

... inbred strains, because the resulting Fl hybrid has known, or very strongly inferred, genotype characteristics relative to the 2 parent strains: For each locus for which the 2 strains have different alleles, the Fl animals will be heterozygotes. Again, random assignment is not possible; the investig ...
studyguidechapter15answers2012
studyguidechapter15answers2012

... 17. During embryogenesis, one of the X chromosomes in every female cell becomes inactivated. What is the name given to this inactivated X chromosome? Barr body 18A. Random inactivation of one of the X chromosomes (X inactivation) occurs in every body cell of female mammals. In a particular breed of ...
BIOLOGY UNIT 6 STUDY GUIDE
BIOLOGY UNIT 6 STUDY GUIDE

... Ry RrYy ...
The Degree of Oneness
The Degree of Oneness

... Although simple dominance is taken directly from nature, it is not the only scheme employed by nature to resolve diploid structures. Another scheme, incomplete dominance, is used by many plant and animal alleles for resolving heterozygous loci, particularly in traits that have more than two simple v ...
mendelian genetics powerpoint 2013
mendelian genetics powerpoint 2013

... The hidden trait returns! F1 generation: Tt x Tt Result? ...
Individual-based neural-network genetic
Individual-based neural-network genetic

... • There is, depending on model complexity, an upper practical limit to how many individuals that can be simulated • In models where the number or biomass of individuals are important and very high, a way around this problem is to treat each individual as a super-individual • A super-individual simpl ...
Evolution of quantitative characters
Evolution of quantitative characters

... 1) DIRECTIONAL SELECTION - selection that causes a directed change in a character. For a quantitative character, the overhead shows the effects of directional selection for increased values of a trait. Directional selection pushes the mean value of the character to the right, by the same type of sel ...
description
description

... Since they physically consist of genes for different types of traits, the X and Y chromosomes cannot truly be called homologous (they are only partially so). Additionally, the presence of a gene for a trait only on the X chromosome has implications for it’s pattern of inheritance. Traits for which t ...
MENDELIAN INHERITANCE
MENDELIAN INHERITANCE

... 1. Mendelian principles (laws) 2. Gene interactions 3. Sex-linked traits 4. Genetic linkage ...
Quantitative-Genetic Models and Changing Environments
Quantitative-Genetic Models and Changing Environments

... Mutation is the ultimate source of genetic variability. However, a large fraction of mutations reduce the fitness of the individuals in which they occur (Chapter 7). The evolutionary consequences of mutations with an unconditionally deleterious effect are manifold and have been the subject of intense ...
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Genetic drift



Genetic drift (or allelic drift) is the change in the frequency of a gene variant (allele) in a population due to random sampling of organisms.The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces. A population's allele frequency is the fraction of the copies of one gene that share a particular form. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation.When there are few copies of an allele, the effect of genetic drift is larger, and when there are many copies the effect is smaller. In the early twentieth century vigorous debates occurred over the relative importance of natural selection versus neutral processes, including genetic drift. Ronald Fisher, who explained natural selection using Mendelian genetics, held the view that genetic drift plays at the most a minor role in evolution, and this remained the dominant view for several decades. In 1968, Motoo Kimura rekindled the debate with his neutral theory of molecular evolution, which claims that most instances where a genetic change spreads across a population (although not necessarily changes in phenotypes) are caused by genetic drift. There is currently a scientific debate about how much of evolution has been caused by natural selection, and how much by genetic drift.
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