regulation of gene expression Flashcards
what is a gene mutation
a change in the base sequence of DNA
what are mutagenic factors
external factors that can increase the rate of mutation
what is deletion mutation
when a nucleotide base is removed from a DNA sequence
what is a substitution mutation
when a nucleotide is swapped out for another one
what is an insertion mutation
when a base is added to a DNA sequence
what is gene expression
when a gene is transcribed and translated, so that is produces a protein
what is a structural gene
codes for a protein that has a function in the cell
what is regulatory gene
codes for a protein that controls structural genes
what is a promoter
a DNA sequence that sits between the regulatory gene and the first structural gene that enables the transcription of structural genes
which enzyme binds to a promoter
RNA polymerase
how is the DNA sequence in prokaryotic cells different than eukaryotic
there is a operator gene between the promoter and the structural genes
what is a transcription factor
the protein that is produced by the regulatory gene that controls the transcription of structural genes
what are the two types of transcription factors in prokaryotes
activator proteins and repressor proteins
where do activator proteins bind to
the promoter DNA sequence, along with RNA polymerase which allows the transcription of structural genes
how do repressor proteins work
they bind to the operator, which means that RNA polymerase is unable to bind to the promoter so the structural genes cant be transcribed
what does an operon contain
cluster of structural genes, operator and a promoter
what does the lac operon do
contains the genes to break down lactose
what is the regulatory gene in the lac operon called
lactose inhibitor gene
