Bacterial Genetics; Mutations Flashcards
How does induced mutation occur?
It’s a result of environmental mutagens
What are mutagens?
?
How do you prevent mutation?
Repair the damaged DNA
What is a silent mutation?
Change in genotype but no change in phenotype (same amino acid translated)
What is a missense mutation?
A change in the genotype and possibly phenotype (different amino acid translated)
Grows slowly
What is a nonsense mutation?
A change in the genotype and possibly phenotype…produces a stop codon.
Null/non functions protein
Is the mutant the auxotroph or the phototroph?
The auxotroph if it’s lacking the nutrient needed to grow
What are the types of spontaneous mutations?
Mistakes; base substitution or addition/removal of nucleotides
Ex: silent mutation, missense mutation, and nonsense mutation
Transposons
What is a mistake in DNA replication
base substitution or addition/removal of nucleotides
Ex: silent mutation, missense mutation, and nonsense mutation
What are transposons?
Segments of DNA that can hop from one site to another “jumping genes
Results in the gene being disrupted…so the gene is no longer expressed.
Can jump into different DNA molecules
Some just hop, others replicates then hops
How many nucleotide pairs does one codon have?
3
What is a frame shift mutation
Adding or subtracting one or two nucleotide pairs
Shift in the reading frame when the sequence is transcribed or translated
Results in a shortened non functional protein (knockout mutation)
What is the importance of mutagens?
Research
Induces genetic mutations
Potential carcinogens
How do cancer cells form?
A mutation in a gene that regulates cell growth means uncontrolled cell growth which means cancerous cell
What are the different types of mutagens?
Chemical mutagens
