CELL DIVISION
MEIOSIS AND GENETIC VARIATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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They change all of the codons from the mutation on down the line, which changes the amino acid sequence
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They insert things that an organism doesn’t need.
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They often delete things that organisms need.
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Insertion and deletions are not any more harmful than substitution mutations.
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Detailed explanation-1: -Because an insertion or deletion results in a frame-shift that changes the reading of subsequent codons and, therefore, alters the entire amino acid sequence that follows the mutation, insertions and deletions are usually more harmful than a substitution in which only a single amino acid is altered.
Detailed explanation-2: -Frameshift mutations arise when the normal sequence of codons is disrupted by the insertion or deletion of one or more nucleotides, provided that the number of nucleotides added or removed is not a multiple of three.
Detailed explanation-3: -Insertion and deletion mutations can have more devastating effects on encoded proteins because, unlike point mutations that can cause a single amino acid in a protein to be changed or cause a protein to be shortened, insertions and deletions have the potential to cause frameshift mutations.
Detailed explanation-4: -Frameshift Mutation If a mutation disrupts this normal reading frame, then the entire gene sequence following the mutation will be incorrectly read. This can result in the addition of the wrong amino acids to the protein and/or the creation of a codon that stops the protein from growing longer.
Detailed explanation-5: -Explain why insertion and deletion are called frameshift mutations using the terms reading frame, codons, and amino acids in your answer. They’re called frameshift mutations because the reading frame is essentially shifted. The editing of a codon causes the reading frame to shift resulting in a different amino acid.