Exam III Review Beyond The Individual gene And Genome Chapter 20 Flashcards
The total of all alleles carried in all members of a population
Gene pool
Only one allele
Monomorphic
More than one allele
Polymorphic
Proportion of all total individuals in a population that have particular phenotype
Phenotype frequency
Proportion of all total individuals in a population that carry a particular genotype
Genotype frequency
Proportion of gene copies in a population that are of a given allele type
Allele frequency
One. The population has an infinite number of individuals. Two. Individuals mate at random. Three. No new mutations appear. Four. No migration into or out of the population. Five. Genotypes have no affect on ability to survive and transmit alleles to the next generation.
Hardy Weinberg assumptions
A group of interbreeding individuals of a single species living in the same time and place
Population
p2 + 2pq + q2 = 1
p + q = 1
Hardy Weinberg proportions
Combining DNA indexing system. 13 unlinked highly variable simple sequence repeat loci.
Codis
Computer program that uses a random number generator to choose an outcome for each probablistic event, i.e. Mating between individuals in a population. Population size is kept constant. Each run represents a possible pathway of genetic drift
Monte Carlo simulation
A change in allele frequency as a consequence of the randomness of inheritance due to sampling error from one generation to the next
Genetic drift
Loss of an allele from the population
Extinction
Only one allele remains in the population
Fixation
A few individuals separate from a larger population and establish a new population that is isolated from the original
Founder effects
Large proportion of individuals die often from environmental disturbances or disease
Population bottlenecks
Variant DNA sequence in and individuals genome that was not present in either parent
Mutation
Mutation that disrupts important functions
Deleterious mutation
Mutations that provide a selective advantage
Beneficial mutations
Mutations without benefit or harm, most mutations
Neutral mutations
Mutation rates appear to be relatively constant so genetically isolated populations accumulate DNA differences at roughly constant rate. Method to determine how long ago populations diversion from a common ancestor using differences in their DNA
Molecular clock
An individual’s relative ability to survive (viability) and transmit it’s jeans to the next generation, reproductive success. Cannot be measured within a single individual. Can be measured by considering all individuals of the same genotype.
Fitness. W ranges from 1 (all individuals survive to reproduce) to 0 (no individuals survive to reproduce)
The process that progressively eliminates individuals whose fitness is lower. individuals whose fitness is higher survive and become the parents of the next generation.
Natural selection
Recessive lethal alleles do not cause death in the heterozygous form because a certain threshold of protein output is maintained. In the homozygous form, the protein output does not meet the threshold, causing death.
Recessive lethal alleles
