comparing genomes Flashcards
what is a genome browser?
bioinformatic tool that allows us to search for info in the genomes of any species
what is an ortholog?
similar sequence in the genomes of different species
what are deletarious changes?
changes that make the resulting organism less well-suited to thrive in its environment
why is genetic recombination important during meiosis?
since both parental chromosomes came from organisms that were able to survive to reproductive age, any change during meiosis is unlikely to be deletarious
the subsequent generations will contain a mixture of the DNA from the 2 parents
genetic diversity is maintained
how does crossing over increase diversity?
it increases diversity by increasing the number of genetically different gametes we can generate
without crossing over –> 2 types of genetically distinct gametes
if ONE crossing over –> 4 types of genetically distinct gametes
what is a chiasma?
location where homologous recombination occurs
what does recombination relies on?
it relies on sequence homology between the two parental chromosome
if two repeated sequences share a high degree of homology, chromosome misalignment may occur
why would a virus’ DNA be inserted permanently into the host cell’s genome?
if that DNA enables the host cell to thrive when it otherwise wouldn’t
why would sequences be selected?
because of its proliferation advantages, the sequence that gives the fastest growth will dominate the population
if a DNA sequence of a gene is identical across many different species, what info does this give us about that sequence?
this means that the sequence is important for function
what are single nucleotide polymorphism (SNP)?
a single position in the genome that is polymorphic in at least some of the population
