Point mutations occur when a single nucleotide in the DNA sequence is changed, and the resulting protein may or may not contain a new amino acid as a result.
One nucleotide is replaced by another in substitution mutations, a form of point mutation that may or may not alter the amino acid sequence of the resulting protein.
How can mutations be classified based on their effect?
As beneficial, harmful, or no effect.
As induced or spontaneous.
As point or deletion mutations.
As heritable or non-heritable.
The text mentions that mutations can be harmful, beneficial, or have no effect.
Option 1 is the correct answer.