module 6 pt1 Flashcards
(46 cards)
what is evolution
a change in allele frequencies in a population over time
what are mutations
random changed in DNA sequences overtime
what are the forms of mutations
substitutions
deletions
insertions
duplications
how can bacterial and archaea genetics exchange genes
horizontal gene transfer
what is wild type
the first one we study from nature
what is a mutant
a cell or virus derived from a wild type that carries a genotype change
what is the medium that allows you to differentiate between different variants of bacteria
macConkey differential media
what is a selectable mutation
easy to detect mutated cells
what is a non selective mutation
requires specific screening - they don’t really produce any noticeable changes
what is a spontaneous mutation
occurs without external intervention
what is an induced mutation
caused environmentally or deliberately
what is a point mutation
only one base pair changes
what is a silent mutation
it has no effect on the protein sequence
what is a nonsense mutation
substitutes a stop codon for an amino acid
what is a missense mutation
results in an amino acid substitution
what is an insertion or deletion mutation
results in a shift in the reading frame
what mutation can be lethal
frameshift mutations (insertion/deletions)
what are homologous genes
genes that all descended from a single ancestral gene - they tend to have similar nucleotide sequences
what are orthologs
homologous genes that share the same function
what are paralogs
single ancestral gene diverges to may different functions in many different organisms
what are gene duplications
thought to drive evolution of gene families and organisms
what occurs more often: insertions/duplications or deletions
deletions
what is evolutionary selection defined by
fitness
what is genetic drift?
random process that can cause gene frequencies to change over time (unpredictable change in the gene pool)
