Nonsense mutations make stop codons. If the mutation is towards the beginning of a gene, then the protein that gets created will be cut short and not function properly. But if it was towards the end, there is still a chance that the protein will still be able to work.
not sure if this is what you need.
I believe its when you <span>silencing one of the two X chromosomes in female cells...
Hope I helped
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Solid inner core, hope this helps, 4300*C.
<span>Damaged dna is excised by endonuclease.
Three excision repair pathways exist to repair single stranded DNA damage: Nucleotide excision repair (NER), base excision repair (BER), and DNA mismatch repair (MMR).</span>