Rate of mutation is extremely low compared to the rate of success of DNA replication, in part because there are several checks during the pocess and even after that tere are mechanisms of DNA repair. For a mutation to occur several "security gates" must be passed. But since populations tend to be large mutations can have an impact over evolutionary time.
It has been estimated (according to our text book) that the average rate of mutation is relatively constant across the tree of life: 1 mutation/10 exp9 nucleotides/cell generation (prokaryotes) and 1 mutation/10 exp9 nucleotides/cell division (eukaryotes).
Mutation is te single force behind evolution and cancer. I can be advantageous, or it can be deletereous.
Quiz #9 Q&As
1. Mention 3 kinds of mutations that promote genome evolution
Point mutation, translocations, deletions, insertions, duplications, inversions...
2. What are ‘regions of synteny’?
Genomic regions with the same genes in the same order in different species
3. Mention a way in which multispecies genome comparisons can be used (a question you can answer with them)
Inferring function of DNA sequences, inferring evolutionary relationships (phylogeny), determining genetic distance...
4. What are Human Accelerated Regions (HARs)?
Genomic regions that are highly conserved accross species but have a high (accelerated) rate of mutation in humans
5. What enzyme is responsible for adding nucleotides to a DNA strand during replication using the other DNA strand as a template?
DNA Polymerase
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