substitution mutations are

Question

always harmful___ true or false
only harmful if a resuting amino acid of the codon is changed___ true or false
never harmful___ true or false
sometimes silent mutations and not expressed___ true or false

Answer 1

1. Substitution mutations are always harmful: False. Substitution mutations can be beneficial, harmful, or neutral depending on the context in which they occur.

2. Substitution mutations are only harmful if a resulting amino acid of the codon is changed: True. If the substitution results in an amino acid change that affects protein function, it can be harmful. However, if it leads to a synonymous mutation (where the amino acid remains the same), it may not affect the organism at all.

3. Substitution mutations are never harmful: False. Some substitution mutations can have detrimental effects, particularly if they alter critical amino acids in proteins or affect regulatory regions of genes.

4. Sometimes silent mutations and not expressed: True. Substitution mutations can be silent (or synonymous), meaning they do not result in a change to the amino acid sequence of a protein, and thus their effects may not be expressed in the phenotype.