DNA and the Structure of Proteins Flashcards
what is a mutation
alteration to the DNA base sequence
often arise spontaneously during DNA replication
what are addition and deletion mutations
where one or more nucleotides (bases) are either inserted or deleted from the DNA sequence
what is a substitution mutation
where one nucleotide (base) in the DNA sequence is replaced by another
what is a duplication mutation
where one or more nucleotides (bases) duplicate and repeat
what is an inversion mutation
where a group of nucleotides (bases) become separated from the DNA sequence, and rejoin in reverse order (flipped)
what is a translocation mutation
where a group of nucleotides become separated from DNA sequence and then inserted into DNA of different chromosome
what is a translocation mutation
where a group of nucleotides become separated from DNA sequence and then inserted into DNA of different chromosome
which mutations are most likely to have a significant impact
insertion, deletion, duplication, translocation
since they produce a frameshift, meaning entire amino acid sequence produced will be different
is a mutation resulting in a change to the amino acid sequence always harmful
no, may be neutral if the resulting change in protein has no effect on the organism. also may be beneficial, which is the basis for evolution and natural selection
what is a mutagenic agent
factors that increase the rate of gene mutation. chemical mutagens such as alcohol and benzene. ionising radiation such as UV and x-ray
