Unit 2 - Genetic Variations Flashcards
a heritable change in genetic code of organism
mutation
organism with a change in this genetic sequence
genotype
strain one derived from nature, not generated in a lab
wild type
are there wild type humans?
no
amount of mutation during replication per kilobase pair
mutation rate
chemical, physical, or biological agents that increase the mutation rate
mutagens
UV light exposure is a type of what?
radiation
this type of radiation is more powerful than UV exposure…..examples x rays and gamma rays
Ionizing Radiation
mutations made deliberately (usually in lab studies)
induced mutation
this type of mutation occurs without human interaction (exposure to things)
spontaneous mutation
If a point mutation is not corrected before replication, the incorrect base will be maintained for how long?
all throughout future generations
subs that do not change the amino acid or reg of a gene
silent mutations
subs that do alter the amino acid or reg
missense mutation
subs that lead to premature stop codons
nonsense mutation
can disrupt replication and transcription by blocking movement of polymerases
structural distortion
3 types of DNA repair systems
- Direct Reversal
- Single strand repair
- Double strand repair
restoring change at same site as original mutation
same site revertant
mutation at different site leads to original phenotype
second site revertant
these two mutants work together to recognize damage
MutS and MutL
this mutant determines which strand is the parent strand
MutH
carry genes for resistance to antiiotics (plasmid type)
Resistance plasmids
confer factors for causing disease (carry toxic genes and enzymes that damage the host cell)
Virulence Plasmids
proteins that inhibit of kill related species or different strains of same species
Bacteriocins
Made in lab and must have own replication and stay in a host of choice
Engineered Plasmids
SOS
Absolute last resort when error free DNA repair systems fail
Sometimes, errors lead to what?
more fit organisms
