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Released STAAR Biology EOC · 2025 · Item 34 · 1 point

Walkthrough: Biology 2025, Item 34

B.7C · Mutations · unscored study

A base sequence of the DNA from a gene is shown. ATC GGC TA Due to a mutation, the base sequence was changed as shown. ATT GGC TA Which type of mutation has occurred in the gene?

  1. Deletion
  2. Substitution
  3. Insertion
  4. Translocation

1. Understand the question

Compare the two DNA sequences base by base and check whether their lengths changed.

Try the question on your own first, then reveal one step at a time.

2. Solve it step by step

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Question, artwork, answer key and rationale: Texas Education Agency released STAAR test. Walkthrough steps written by TEKSForge. Studying here does not change your mastery or scores.