Altering sequence of bases can alter the protein (20) Flashcards
What is a mutation?
alteration to the DNA base sequence
What are the 6 types of mutation?
addition (insertion)
deletion
substitution
duplication
inversion
translocation
What is an addition (insertion) mutation?
when 1 or more nucleotides are inserted into the DNA sequence
What is a deletion mutation?
when 1 or more nucleotides are deleted from the DNA sequence
What is a substitution mutation?
when 1 nucleotide in the DNA sequence is replaced by another
What is a duplication mutation?
when 1 or more nucleotides duplicate and repeat
What is an inversion mutation?
when a group of nucleotides detach from the DNA sequence and then rejoin inverted
What is a translocation mutation?
when a group of nucleotides detach from the DNA sequence on one chromosome and are inserted into the DNA of another chromosome
What are 2 possible consequences of a mutation resulting in a change to the amino acid sequence?
- neutral if the resulting change in protein has no effect on the organism
- beneficial e.g. for evolution and natural selection
What 4 types of mutation are most likely to have a significant impact?
insertion (addition)
deletion
duplication
translocation
Why are insertion (addition), deletion, duplication and translocation mutations most likely to have a significant impact?
they cause a frameshift meaning the entire amino acid sequence produced will be different
What 2 types of mutation are most likely to have only a small impact? (quiet mutations)
substitution
inversion
Why are substitution and inversion mutations most likely to have only a small impact?
they only alter 1 or very few triplets so the amino acid sequence might not be affected due to the degenerate nature of the genetic code
What are 2 types of mutagenic agent?
chemical mutagens
ionising radiation
What are 2 examples of chemical mutagens?
alcohol
benzene
