W4 Mutations and Repair Flashcards
what is point mutation
change 1 nucleotide
what is the 3rd position of codon called
wobble
why is the wobble so easy to change
high redundancy
what is a point mutation
single nucleotide change
what is the wobble
3rd position of codon
why do point mutations occur on the wobble
most redundancy
how does chronic myeloid leukaemia occur
translocation between chromosome 9 and 22
what is Robertsonian translocation
when a majority of chromosome is added to another chromosome
what is chromosomes are required for Robertsonian translocation
acrocentric or telocentric chromosomes
what does it mean if someone is aneuploid
have an irregular chromosome number
what is polyploidy
duplication of single chromosome
what can happen due to polyploidy of chromosomes
non disjunction
what chemical causes meiosis errors in plants
colchicine
what are the steps to mutation base excision repair
- DNA glycosylase sees DNA damage
- AP endonuclease removes sugar backbone
- removed damaged nucleotide is filled with DNA polymerase and ligase
how is mismatched nucleotides detected
single strand nicks on DNA strand
how are double stranded breaks fixed
non-homologous end joining
what is a mutation that doesn’t change the amino acid
Synonymous mutation
what are the steps of homologous recombination
- nuclease digest 5’ end to create overhangs
- unpaired single stranded DNA pairs with the complimentary template strand
- undamaged DNA is used as template
- the invading strand is then extended by DNA polymerase
- gaps in new DNA strands are joined by DNA ligase
how do bacteria resists viruses
- virus invades cell
- spacer seq come from viral RNAs
- spacer embeds into genome
- spacers are transcribed into CRISPR RNA
- bind to cas proteins
- guide RNA and cas protein target complementary seq then case dsDNA break
what is lineage tracing
track origins of a cell
whats the role of the guide RNA
find specific sequences of DNA
what is GFP
green fluorescent protein
how does SCAR-TRACE use mutations
more mutations shared means more closely related
what does cystic fibrosis do
- due to mutation to CFTR gene more mucus is produced
- since CFTR regulates the movement of water and salt in cells
how does cystic fibrosis effect the lungs
- block offs alveoli
- creates environment for bacteria -> infections
- can cause inflammatory response
