mutatitions Flashcards
wild-type
natural state of an organism from nature
genotype
hereditary genetic info
phenotype
observable traits - expression of genotype
mutation
change in genotype
point mutation
changes a single base in a nucleotide sequence, can be minimal or severe based on location
point mutation
changes a single base in a nucleotide sequence, can be minimal or severe based on location
silent mutations
a point mutation that doesn’t change the amino acid
redundancy/wobble effect
missense mutations
point mutation that results in a different amino acid in a chain
nonsense mutation
point mutation that results in a new stop codon
deletion mutations
can remove sections of genes, promotors, terminators
we assume unless otherwise stated that this DOESN’T result in a frame shift, 3 base pairs exactly are deleted
frame shift mutation
deletion mutation that results in a shift of the reading frame - very severe generally
operons
share a promoter and terminus but include multiple coding regions for different genes
positive regulation
reg protein binds to operator and increases transcription
negative regulation
reg protein binds to operator and decreases transcription
review of lac operon
lacI a repressor so binds to promoter and prevents transcription of lacZYA, but when lactose is present it causes allosteric changes to the reg protein lacI which prevent it from binding to the operator, therefore lac ZYA are transcribed
review of mal operon
malT is an activator, but cannot bind to operator when maltose is absent therefore low transcription of malPQ
constitutively expressed genes
not regulated, transcribed at all times
non-constitutively expressed genes
regulated, rate of transcription depends on the environment
what would missense mutation in functional region of lacI mean for transcrip of lac operon
high levels of transcription, missense in functional means it wont be able to bind properly to operator and act as a repressor therefore lac is expressed
