linkage equilibrium and sex Flashcards
the specific location of a gene or DNA sequence on a chromosome
locus
different versions of the same gene that differs only in their base sequence
allele
changes in the relative frequencies of traits are tied ti changes in the relative frequencies of
alleles
2 genes that occur on the same chromosome and are sufficiently close to each other that crossing over should be rare are ____ _____
physically linked
in linkage, we have to consider all frequencies as well as
chromosome frequencies
the main questions of linkage
will selection and locus a interfere with selection at locus b?
how might differential selection affect our ability to employ HW equilibrium models?
when the genotype of a chromosome at one locus is independent of its genotype at the other locus
linkage equilibrium
any nonrandom association between a chromosomes genotype at one locus and its genotype at the other locus
linkage disequilibrium
meiosis, producing male and female gametes, fertilization and production of diploid zygote
sexual reproduction
a mode of reproduction wherein offspring develop from unfertilized eggs
parhtenogenesis
if asexually reproducing organisms have such a numerical advantage, why aren’t they more common in nature?
sex has the advantage of genetic recocmbination
meta analysis of experimental results suggest that in general , selection favors
genetic recombination
deleterious mutations accumulate in asexually reproducing populations often dooming them, this is known as
Mueller’s ratchet, or the genetic load
what affect does genetic recombination have on linkage disequillibirum?
it reduces it
why is sex so great? 4
1 genetic recombination increased via sex
2. genetic recombination reduces linkage disequilibrium
3. benefits of sex magnified under genetic drift an mutation
4. sex provides enormous benefits when environments are subject to change
