Mutation & Variation Flashcards
intergenic
regions of the chromosome between genes
effects of synonymous mutations
do Not change protein sequence
effects of nonsynonymous mutations
change in protein sequence
are exons or introns more sensitive to selective pressure
exons - because they are expressed
polymorphism
a locus at which multiple genotypes exist in the population
introns and intergenic regions can affect genes because
they can have regulatory information controlling gene expression etc
recombination
reshuffling of parents’ chromosomes before passing them on to offpsring
allele frequencies
the relative rates at which different alleles for a single locus are found in the population
segregation
separating 2 alleles for a trait, and passing on only one from each parent
asexual reproduction can achieve _______ but not _______
recombination; segregation
linkage disequilibrium
caused by random placement of alleles -> two close alleles have a low change of being recombined with another allele between them, meaning that they will be linked when they are passed on, affecting the randomness of segregation
hardy-weinberg null hypothesis
random free mating, no migration, equally fit individuals
pleiotropy
a gene affects multiple functions
can be beneficial for 1 function and deleterious for another
probably applies to most genes
copy number variant mutations
sections of the genome are repeating varying numbers of times
homeotic mutations
can transform one body part into another
ex. fly antennae into legs
usually near the top of a gene expression cascade
germline mutations
appear in the reproductive cells and can be inherited
somatic mutations
occur in body cells, impact the individual but not their offspring
mutation rate =
mutation per site per generation
OR mutations per genome per generation
how to estimate mutation rate
generations between individuals and # mutations accumulated in a neutrally evolving stretch of the genome
mutations are distributed ______ in the genome
randomly
most common mutation
C > T point mutations
cytosines are often methylated and spontaneously lose an amino group, becoming identical to thymine
maternal effects
mother donates proteins to the egg even if the egg cannot make those proteins itself
cultural inheritance
some traits can be taught and are therefore passed on
(article about niche construction)
