Population Genetics I Flashcards
What is a genetic cause of phenotypes?
Phenotypes with an underlying genetic cause do not have to be under the control of a single gene with clear Mendelian inheritance
What is an environmental influence on phenotypes?
Study of population genetics - the genetic based of evolution can sometimes be difficult because the genotypes do not uniquely determine phenotypes
What is heritability?
The proportion of o served differences of a trait among individuals of a population that are due to genetic differences
Outline the meaning behind population genetics?
-study of genetic variation within populations
What is a gene pool?
Sun of all alleles in a population
What does a gene pool contain?
The variation that produces the differing phenotypes on which agents of evolution act
What are the 6 assumptions made to meet the hardy-Weinberg equilibrium?
1-mating is random
2-population size is very large
3-no migration between populations
4-no mutations
5-natural selection does not affect the alleles under consideration
6-all members of the population breed
If all conditions of the hardy-Weinberg equilibrium are met, what 2 results follow?
1)frequencies of alleles at a locus will remain constant from generation to generation
2)genotype frequencies can be predicted from allele frequences
What is the cause of sickle cell anaemia ?
Those with two copies of the sickle cell allele have lower life expectancy
What are 5 causes of disequilibrium?
-genetic drift
-mutation
-mating choice
-migration
-natural selection
Define the meaning behind random genetic drift
- variation between generations due to random sampling
What are 4 factors that can limit the rate of loss of genetic variation due to genetic drift?
(1)large population size
(2)mutation
(3)natural selection
(4)migration between subpopulations
