Question

review the passage about the effects of the krt13 gene mutation.
keratin are strong proteins that provide structure and protection for many tissues in the human body. for example, the tissue on the inside of the mouth, called epithelium (ep-i-theel-i-um), is protected by a tough layer made of many types of keratin proteins connected together. one type of keratin protein is encoded by the krt13 gene.
a certain person had a mutation in the krt13 gene. compared to the krt13 gene without a mutation, the mutated krt13 gene encoded a form of the keratin protein with a different structure.
this different form of the keratin protein could not connect to other keratin proteins. the person with the mutation had mouth epithelium that was easily damaged by simple activities like eating and brushing teeth.
complete the sentence.
the mutation caused the krt13 gene to encode a form of the keratin protein that
with other keratin proteins.
could not connect
was more likely to connect

Explanation:

The passage clearly states that the mutated KRT13 gene encoded a keratin protein that “could not connect to other keratin proteins”. This is directly provided in the text, so we just need to refer to that specific statement.

Answer:

could not connect