Study sets, textbooks, questions
Upgrade to remove ads
Bio 106 Chapter 21 Evolution
Terms in this set (48)
trait that increases fitness in particular environment
Allele and genotype frequencies
Genotype frequencies are the frequencies of the homozygous dominant (AA) heterozygous (Aa) and homozygous recessive (aa). If you're using population genetics, then they are the p^2, 2pq, and q^2 values.
Allele frequencies are the frequencies of each allele, dominant (A) and recessive (a). In population genetics these are p & q.
same as directional selection, but the competitive element is removed (practiced by humans through breeding)
variation occurs across a spectrum (human height)
concieved the idea of natural selection
all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual's ability to compete, survive, and reproduce.
clear alternative states (Mendel's experiments - only two colored peas)
helps determine evolutionary relationships by seeing how similar sequences are
Change in populations over time
Fisher, Ronald A
neo-Darwinian synthesis; contributed teh analysis of variance (ANOVA)
a measure of the extent to which the individual's genotype is represented in the next generation
method for separation and analysis of macromolecules (DNA, RNA and proteins) and their fragments, based on their size and charge.
movement of alleles from one population to another
all the alleles present in all individuals in a species
a change in the frequency of an allele due to the random effects of small population size
variation in individuals due to differences in the genes that are transmitted from parents to their offspring
set of alleles that determines the expression of a particular characteristic or trait (phenotype).
There can be no differences in the survival and reproductive success of individuals
No migration within populations
There can be no mutation
The population must be sufficiently large to prevent sampling errors
Individuals must mate at random
form of balancing selection that ensures that both alleles remain in the population at intermediate frequencies
1. the Law of Dominance
2. the Law of Segregation
3. the Law of Independent Assortment
movement of individuals from one population in another
combination of Darwinian and Mendelian concepts which is our current theory of evolution evolution and common descent
occurs when populations have diverged genetically
correlation between the time two species have been evolutionarily separated and the amount of genetic divergence between them
a change in DNA sequence, utlimate source of variation
when there is variation within a population, and when that variation can be inherited, the variants best suited for growth and reproduction in a given environment will contribute disproportionately to the next generation
occurs when individuals do not mate randomly
Patterns of selection: Stabilizing,
• Stabilizing selection- natural selection that maintains the status quo and acts against extremes
• Directional selection- natural selection that leads to a trait over time
• Artificial selection- same as directional selection, but the competitive element is removed (practiced by humans through breeding)
• Disruptive selection- natural selection that operates in favor of extremes and against intermediate forms
the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.
group of species in a geographical area
study of allele frequency distribution and change under the influence of the four main evolutionary processes: natural selection, genetic drift, mutation and gene flow. Also recombination
two DNA molecules exchange genetic information, resulting in the production of a new combination of alleles
ability for offsrping to reproduce
promotes traits that increase an individual's access to reproductive opportunities
increases individuals reproductive success
consists of individuals that can exchange genetic material through interbreeding
Types of selection: Positive, Negative, Balancing
• Positive selection- natural selection that increases the frequency of a favorable allele
• Negative selection- natural selection that decreases the frequency of a harmful allele
• Balancing selection- natural selection that acts to maintain two or more alleles in a population
Theory of Evolution by Natural Selection
natural selection may cause evolution
developed natural selection with darwin
Explain what biological evolution is and why it is considered to be one of the most important ideas in biology.
What is Hardy Weinberg Equilibrium? What assumption does it make? Why is it important? Know the equation and be able to use it to predict allele frequencies
from genotype or phenotype frequencies and vice versa. Be able to evaluate whether populations are in HWE.
FREQUENCIES FROM ALLELE
FREQUENCIES; null hypothesis = Situation when allele frequencies
do NOT change in a population - if not true evolution has occured
p + q = 1
p^2 + 2pq + q^2 = 1
What is Population Genetics? What sorts of questions does this discipline address? How can it make inferences about evolution?
study of the frequency and interaction of alleles and genes in populations; includes HWE. Use HWE to determine if evolution ahs occured
What processes cause genetic variation? Discuss relative importance of mutations
and recombination. What causes recombination?
Mutations (deleterious, neutral, adventageous)and Recombination: reshuffling during sexual reproduction
What tools do scientist use to estimate genetic variation? Give examples discussed in class. Understand how to determine allele frequencies based on various traits, gel electrophoresis or DNA differences.
Ufinding genotype/allele frequences by hwe, observable traits, gel electrophoresis (proteins, dna), and dna sequencies
Why is it so important to estimate allele frequencies in populations?
In order to see the degree of variation in a species
What are the major contributions of Darwin's Origin of Species?
natural selection results in change in allele frequencies
What was the controversy between "Mendelians" and "Biometricians?" Explain what Modern Synthesis is.
mendelian genetics: discrete trais biometricians: variation in nature RA Fisher proposed many genes contribute to a single trait = basis of synthesis
b/n Mendel's Law and Darwin's theory
Explain how natural selection leads to evolution and adaptation. How are the other factors (migration, mutation, mating patterns, and genetic drift) different or similar
in their effect on allele frequencies and genotype frequencies?
natural selection is the only mechanism that leads to adaptations
mutation causes allele frequency changes while migration and genetic drift do no
What is the impact of gene flow on genetic make up of populations?
between bottleneck and founder effect.
alleles move to another population - reduces genetic divergence.
RANDOM change in allele
¡Strongly affected by
Bottleneck (natural disasters)
§ population reduced drastically
§ establishment of a new
population with few individuals
Recommended textbook explanations
Miller and Levine Biology
Joseph S. Levine, Kenneth R. Miller
Fundamentals of Biochemistry: Life at the Molecular Level
Charlotte W. Pratt, Donald Voet, Judith G. Voet
Fundamentals of Biochemistry
Charlotte W. Pratt, Donald Voet, Judith G. Voet
Campbell Biology (AP Edition)
Cain, Jackson, Minorsky, Reece, Urry, Wasserman
Sets found in the same folder
Ch 23 Bio 226
Ch. 21 Learning Curve
Bio Lecture 14
BIO 171 Lecture 14
Sets with similar terms
Chapter 21 Evolution
Chapter 21 Evolution
BIO- Ch. 21: Mechanisms of Evolution
Bio 3 test review
Other sets by this creator
Lily French Ch4
Instrumentation Test 3
SPAN 3040 - Prueba 3
Other Quizlet sets
Brain, Behavior, and Immunity Exam 2
Chapter 11 and 12
MKT 4080 Terms Ch. 4