THE MOLECULAR BASIS OF INHERITANCE
GENE MUTATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the addition of one or more nucleotides.
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the removal of one or more nucleotides.
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the replacement of one or more nucleotides.
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When a codons shift ____ nucleotides are regrouped due to a mutation.
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Detailed explanation-1: -Substitution, as related to genomics, is a type of mutation in which one nucleotide is replaced by a different nucleotide. The term can also refer to the replacement of one amino acid in a protein with a different amino acid.
Detailed explanation-2: -Substitution. This type of variant replaces one DNA building block (nucleotide) with another. Substitution variants can be further classified by the effect they have on the production of protein from the altered gene.
Detailed explanation-3: -With base substitution mutations, only a single nucleotide within a gene sequence is changed, so only one codon is affected (Figure 1).
Detailed explanation-4: -Substitution mutation is sometimes referred to as point mutation. However, point mutation is defined particularly as a type of mutation involving a change of only one nucleotide. See also: transversion. transition.
Detailed explanation-5: -A substitution is a mutation that exchanges one base for another (i.e., a change in a single “chemical letter” such as switching an A to a G). Such a substitution could: change a codon to one that encodes a different amino acid and cause a small change in the protein produced.