8.4 Flashcards
What is a codon?
A sequence of three nucleotides in mRNA that specifies an amino acid.
What is an anticodon?
A sequence of three nucleotides in tRNA that pairs with a corresponding codon in mRNA.
What is translation?
The process of synthesizing proteins from mRNA.
What is a start codon?
The codon that signals the beginning of protein synthesis, typically AUG.
What is a stop codon?
A codon that signals the termination of protein synthesis.
What is a positive transcription factor?
A protein that enhances the transcription of a gene.
What is a negative transcription factor?
A protein that represses the transcription of a gene.
What does affinity refer to in the context of transcription factors?
The strength of binding between a transcription factor and its target DNA sequence.
What is a mutation?
A change in the nucleotide sequence of DNA.
Role of mRNA in translation?
Carries the genetic information from DNA to the ribosome for protein synthesis.
Role of tRNA in translation?
Brings amino acids to the ribosome and matches them to the codons in mRNA.
tRNA has an anticodon that pairs with the codon in mRNA.
Role of rRNA in translation?
Structural and functional component of ribosomes, facilitating the translation process.
Types of mutations include:
- Point
- Silent
- Missense
- Nonsense
- Frameshift
What is a point mutation?
A change in a single nucleotide in the DNA sequence.
What is a silent mutation?
A mutation that does not change the amino acid sequence of a protein.
What is a missense mutation?
A mutation that results in the substitution of one amino acid for another in a protein.
What is a nonsense mutation?
A mutation that creates a premature stop codon in the protein sequence.
What is a frameshift mutation?
A mutation caused by insertions or deletions that shift the reading frame of the genetic code.
How does gene regulation affect protein production?
It is affected by positive/negative transcription factors and affinity strength.
Use the codon chart to translate mRNA into an amino acid sequence: What is the first step?
Identify the start codon in the mRNA sequence.
Identify different types of mutations.
Point, silent, missense, nonsense, frameshift.
