TEST 2: Regulation of Transcription Flashcards
What makes cells different from each other if all cells of a single individual have the same DNA?
The proteins they make!
(red blood cells, transcribe hemoglobin gene, stomach cells transcribe Pepsin gene)
Define housekeeping protein
Housekeeping proteins are made in all cells and carry out functions that are required for every cell to function normally
Both red blood cells and stomach cells transcribe ribosomal gene
Define activator protein
Activator proteins bond to promoter and allow RNA polymerase to bind
Define repressor proteins
Repressor proteins fine to promoter to prevent RNA polymerase from binding
How do you activator and repressor proteins influence whether a gene will be transcribed
One enhances transcription while the other inhibits it, both are crucial for gene regulation, allow allowing cells to control which genes are expressed, and when and insuring the right proteins are made at the right time
Define mutation
Any change in the nucleotide sequence of DNA that can occur within a gene or outside it
Where do mutations come from?
A mistake that occurs when the DNA is copied in preparation for cell division
Environmental conditions, including exposure to certain chemicals, and some types of radiations
Three types of mutations talked about in class
Insertion, deletion, nucleotide substitutions(point mutations)
How is DNA altered with an insertion mutation
One or more nucleotide pairs are inserted into the DNA molecule and alters the reading frame of gene
How is DNA altered by a deletion mutation?
One or more nucleotide pairs are removed from the DNA molecule which leads to different protein product like an insertion
How is DNA altered by a nucleotide substitution?
The replacement of one nucleotide by another in the DNA template strand, possibly changing a codon
How will the number of nucleotides that are either inserted or deleted from a gene affect the protein that is ultimately made from this mutated gene
Depending on whether the number of nucleotides, inserted or deleted as a multiple of three, there will be a frame shift mutation (alters, reading frame of gene)
