Question

dna mutations
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ji wants to write an example of a frameshift mutation using the following sentence: the cat saw the rat. which sentence best shows a frameshift mutation?
thc ats awt her at.
cat the saw rat the.
eht tac was eht tar.
the the cat saw the rat.
mark this and return save and exit next submit

Explanation:

A frameshift mutation occurs when nucleotides are inserted or deleted, shifting the reading frame. In the original sentence "THE CAT SAW THE RAT", each word is a 3 - letter "codon".

• For "THC ATS AWT HER AT": The deletion of the second 'E' in "THE" shifts the reading frame. Now, we have "THC" (instead of "THE"), "ATS" (instead of "CAT"), etc.
• "CAT THE SAW RAT THE" is just a re - arrangement of the original words, not a frameshift.
• "EHT TAC WAS EHT TAR" is a substitution (reversal of letters in each "codon"), not a frameshift.
• "THE THE CAT SAW THE RAT" is an insertion of "THE", but it's not a frameshift as the reading frame for the subsequent words is not shifted in the same way as a single - nucleotide deletion/insertion would.

Answer:

THC ATS AWT HER AT.