• 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
Inheritance_and_Gregor_Mendel
Inheritance_and_Gregor_Mendel

... Dominant traits are represented by capital letters (T) while recessive traits are represented by lower case letters (t). ...
Evolution 1/e
Evolution 1/e

... allele get sickle cell anemia.  Individuals with only one copy of the allele (heterozygotes) get sickle cell trait (a mild form of the disease)  Individuals with the sickle cell allele (one ...
8. Conservation genetics
8. Conservation genetics

... § Is based on changes in allele frequencies that occur between two or more temporal samples taken from a small population § Larger changes in allele frequencies in smaller populations because of genetic drift § Effective population size could be estimated on the basis of the amount of change ...
The Hardy-Weinberg equation can test whether a population is
The Hardy-Weinberg equation can test whether a population is

... population is evolving  The shuffling of alleles that accompanies sexual reproduction does not alter the genetic makeup of the population. – No matter how many times alleles are segregated into different gametes, and united in different combinations by fertilization, the frequency of each allele in ...
How are Traits Passed from Parents to Offspring
How are Traits Passed from Parents to Offspring

... Name___________________________________________________ Date______________________Hour_______ How are Traits Passed from Parents to Offspring? A trait is a characteristic such as color or size that is inherited by an offspring from its parents. The genes that control a trait come in pairs, one gene ...
Heredity
Heredity

... • Chromosomes are made up of many genes joined together like beads on a string. • The chromosomes in a pair may have different alleles for some genes and the same allele for others. ...
Honors Evolution Power Point 201
Honors Evolution Power Point 201

... Patterns of Evolution • 1. Coevolution: the change of two or more species in close association with each other is called coevolution – Predators and their prey sometimes co-evolve • Ex: “tropical region” bats feed on nectar – Bats have slender muzzle and long tongue that help them to feed,flowers a ...
C15_Chan
C15_Chan

... Now able to assess ~2.5M SNPs in a genome all at once Various platforms are available for mostly common SNPs (>5 % in the general population) ...
Hardy Weinberg Equilibrium Problems
Hardy Weinberg Equilibrium Problems

... 11. Sickle-cell anemia is a disease caused by the inheritance of a dominant sickle gene. This gene is codominant with the normal hemoglobin gene. In a certain African tribe, 4% of the population is born with sickle-cell disease having inherited both dominant sickle genes. What is the percentage of i ...
Level Guide Chapter 9
Level Guide Chapter 9

... Mendel used cross-pollination to find out what would happen if he crossed two plants with different forms of a trait. When Mendel used ratios to compare the number of white flowers to the number of purple flowers produced in the second generation, he found that the ratio of purple flowers to every w ...
11.1 Genetic Variation Within Population
11.1 Genetic Variation Within Population

... Genetic variation in a population increases the chance that some individuals will survive. • Genetic variation leads to phenotypic variation. • Phenotypic variation is necessary for natural selection. • Genetic variation is stored in a population’s gene pool. – made up of all alleles in a population ...
Charles Darwin
Charles Darwin

... • Theory explains the history of life • 2 types: • Microevolution • Macroevolution ...
Document
Document

... Summer squash can be found in three shapes: disk, spherical, and elongate. In one experiment, two squash plants with diskshaped fruits were crossed. The first 160 seeds planted from this cross produced plants with fruit shapes as follows: 89 disk, 61 sphere, and 10 elongate. What is the mode of inh ...
Probability and Heredity
Probability and Heredity

... how likely it is that an event will occur  Mathematics of probability – In a coin toss there are 2 possible outcomes. The coin can land heads up or tails up. Each result has an equal chance of occurring – 1 out of 2.  Probability can be expressed as a ratio, fraction orpercent – 1:2, ½, or 50% ...
Lecture Summary Concepts
Lecture Summary Concepts

... Jeremy Robertson Lect 1 and 2 Which of the following best describes the logic of hypothesis based science? 1. If I generate a testable hypothesis, tests and observations will support it. 2. If my prediction is correct it will lead to a testable hypothesis. 3. If my observations are accurate they wi ...
probability laws
probability laws

Pedigree Analysis
Pedigree Analysis

... well for organisms that have large numbers of offspring and controlled matings, but humans are quite different: 1. small families. Even large human families have 20 or fewer children. 2. Uncontrolled matings, often with heterozygotes. 3. Failure to truthfully identify parentage. ...
Pedigree Analysis
Pedigree Analysis

... well for organisms that have large numbers of offspring and controlled matings, but humans are quite different: 1. small families. Even large human families have 20 or fewer children. 2. Uncontrolled matings, often with heterozygotes. 3. Failure to truthfully identify parentage. ...
Lecture #6: The Modern Synthesis – Wednesday 11 July
Lecture #6: The Modern Synthesis – Wednesday 11 July

Biology 2108 Laboratory Exercises: Variation in
Biology 2108 Laboratory Exercises: Variation in

... each population cage four generations after the population cages were established. The number of normal wing flies and the number of vestigial wing flies were tabulated for each cage. Between 100 and 125 flies were tabulated in each cage. Both cages were started with parents that were heterozygotes ...
CHS Honors Bio Final Exam Review Packet 2013
CHS Honors Bio Final Exam Review Packet 2013

Understanding mismarks
Understanding mismarks

... over the entire surface of the coat. Labs that carry an allele other than “As” at the A locus, have a greater likelihood of expressing more white hairs than those Labs that do carry “As”. Therefore, although all Labs should be homozygous for the S allele at the S gene locus, some may still express w ...
Directional Positive Selection on an Allele of Arbitrary
Directional Positive Selection on an Allele of Arbitrary

... examining the trajectory of the allele conditional on fixation. For strong selection, an example is provided in Figure 2a. When the allele is rare, it is found almost exclusively in heterozygotes. Thus, if it is recessive (e.g., h ¼ 0.1), it will be hidden from selection in the early phases and take ...
Agenda 06/12/06 1. Notes - Genetics 2. Practice Problems 3
Agenda 06/12/06 1. Notes - Genetics 2. Practice Problems 3

... Example of Recessive Inheritance • If a pea plant has WW or Ww they have a dominant gene and will have purple flowers. • However if the pea plant has two recessive genes ww, their flowers will be white. ...
Hardy-Weinberg Lesson Plan 4
Hardy-Weinberg Lesson Plan 4

... 3. Afterward, we’d have the students try some example problems. We’d discuss how to solve a problem as a class, the goal of the discussion will be to ensure that students realize that they have to solve in terms of the recessive allele, q, and work backwards to get other values. Once that’s been ens ...
< 1 ... 330 331 332 333 334 335 336 337 338 ... 511 >

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.
  • studyres.com © 2026
  • DMCA
  • Privacy
  • Terms
  • Report