Unit 8.4 Flashcards
What is the definition of codons?
A sequence of 3 nuecleotides on messenger RNA.
What is the definition of anticodons?
On + RNA base pairs with codon.
What is the definition of translation?
Process of translating the sequence of a messenger RNA molecule to a sequence of amino acids during protein synthesis.
What is the definition of start codon?
The first codon in the transcribed mRNA that undergoes translation.
What is the definition of stop codon?
A codon that signals the termination of the translation process of the current protein.
What is the definition of positive transcription factor?
A protein that binds to DNA at a specific site and actively increases the rate of transcription of a gene.
What is the definition of negative transcription factor?
A protein that binds to DNA and inhibits the process of transcription
What is the definition of affinity?
The strength of the attraction between two substances such as two chemicals, or an antigen and an antibody.
What is the definition of mutation?
Change in the base sequence (order of A,T,C and G’s) in a molecule of DNA.
What is the role of mRNA in translation?
Contains message/code for amino acid sequence.
What is the role of tRNA in translation?
Transfers amino acids, contains anticodon that pair with mRNA codons to put a.a in the correct order
What is the role of rRNA in translation?
Facilitates match of mRNA and rRNA and joins amino acids to synthesize proteins.
What is silent point mutations?
This is when something is substituted but it produces the same amino acid.
What is missense point mutations?
This is when it codes for another amino acid, but still substitutes only one amino acid in.
What is nonsense point mutations?
This is when something is substituted in and it causes the amino acid to be a stop codon which then stops all the codons after it.
What are framshift mutations?
Insertions or deletions that shift the reading frame. This kind of mutation then changes everything from the framshift site.
How is protein production affected by positive/negative transcription factors?
More positive transcription factors=more proteins. Less of these then results in slower protein production. If you have a lot of negative transcription factors that then prevents the proteins from being made.
How is protein production affected by affinity strength?
If the affinity is very strong between the positive factors, like transcription factors and RNA pol then the protein production is increased. If the affinity between negetive transcription factors is increased, that will reduce production.
